Thursday, January 24, 2013
The enormity of the Nuclear Energy
The term "nuclear" is a word that is very scary for some people. This is not surprising since the term was introduced to the world through the destruction of two Japanese cities, Hiroshima and Nagasaki. The destruction of the two cities end the upheaval of World War II when Japan surrendered unconditionally to the Allies.
Bombs were dropped on Japan, is the principle of the fission reaction isotope splitting heavy elements into a two bermasa core being. Fission reaction can take place spontaneously and induction takes place (shot using a particle core) typically uses neutrons. Nevertheless, not all isotopes of the heavy elements undergo fission. Fission reactions release energy in the form of a major radiation and kinetic energy of fission results.
Fission reactions that occur in a nuclear bomb can not be controlled, so that once a burst of energy produced will destroy all that is to reach a stable state. While the fission reaction in a nuclear reactor can be controlled by absorbing excess neutrons for the fission chain reaction can be stopped.
Energy generated from nuclear reaction or a nuclear reaction or cleavage nuclei of other elements to form a more stable called nuclear energy. The energy produced in a nuclear reaction is calculated peratom, meaning one atom alone can produce energy.
Suppose calculate the amount of energy generated from the combustion of 1 gram of uranium-235.
clip_image002
clip_image004
clip_image006
Based on experiments obtained, each burning one atom of uranium-235 obtained an energy of 200 MeV. So the energy generated from the combustion of 1 gram of U-235 are as follows.
E = 2.56 x 23 x 200 atoms x 200 MeV / atom
= 5.12 x 23 MeV
Since 1 MeV = 3.83 x 10-14 calories (cal), then
E = 5.12 x 3.83 x 10-14 x1023 cal
= 1.96 x 1010 cal
If the energy compared with burning powder 50 grenade TNT (trinitrotoluene) calculation is as follows.
Energy produced 50 grams of TNT = 50 000 cal = 5 x 104 cal
So burning 1 gram of uranium equal to burning as much TNT
= 50 (2 x 1010) / 5 x 104 g
= 20,000,000 grams of TNT
= 20 tons of TNT
So the energy produced 1 gram of uranium-235 equal to the energy released an explosion of 20 tons of TNT.
Therefore, the enormous energy of the combustion reaction of the core can be utilized for the welfare of mankind.
Unfortunately until now Indonesia has not used this enormous energy for the welfare of the people, despite having several nuclear reactors. This may be because we are afraid of the negative effects caused by nuclear energy.
Keep in mind that as long as nuclear energy is handled correctly, negative things had been feared would never happen. Many countries whose economies are far more advanced than Indonesia for using nuclear energy. Because of this the owner of this blog would like to state
"STOP LOOK AND LISTEN Indonesiaku JUST SOMETHING NEGATIVE SIDE OF COURSE, BUT THE NEGATIVE SIDE TEROBOSI AND SKIP TO FIND THE POSITIVE SIDE DURING THIS EVEN IF WE HAVE BEEN untouched REALIZE HE WAS OUR MENATIKAN"
* High School CLASS II Fierce Nuclear Energy, nuclear energy, radioactive, radioactive elements, uranium
Photoelectric Effect
1 Comment Posted by Emel Seran on July 20, 2011
One of the facts that support the theory of Max Planck that the photoelectric effect (Max Planck read Theory: The Basics Vis Spectrophotometer, UV, UV-Vis). Einstein in 1905 using Planck's theory to explain the photoelectric effect. The photoelectric effect is bouncing or release of electrons from a metal surface by radiation or photons elektromatik. Electrons are released from the metal surface is called photoelectron. In the photoelectric effect experiment can be done using the tool as shown in Fig.
photoelectric effect wanibesak
Equipment in Figure consists of a hollow tube and at each end of the tube is placed a thin sheet of metal. In two metal plates connected to a multimeter or avometer for measuring strong currents caused. Initially no current caused.
But when the light of certain frequencies is given to one metal plate will give rise to an electric current that can be observed in the multimeter. The electrical current that arises because, when the metal is light with a certain frequency, the electrons on the surface of metal atoms can bounce or detached then move towards other metal plates.
Electrons on a metal surface can bounce as light or photons have a certain energy, which can be calculated with the equation E = hv. Minimum energy required to bouncing electrons from a metal surface is called the energy or frequency threshold (x0).
If the photon's energy is below the energy threshold, then no electrons that bounce. This is due to the photon energy can not beat gravity core of the electrons to be released.
For the bouncing electrons from the metal surface does not depend on the intensity or brightness of the light but it depends on the frequency of light. Although the light intensity on the surface of the metal has a weak (dim), but has an energy above the threshold energy electrons can bounce off the metal surface with a certain speed.
If the photon's energy is above the threshold energy the electrons will bounce and the remaining energy is converted into kinetic energy for the electrons that bounce. Based on the experiments acquired a number of facts that are characteristic of the photoelectric effect as follows.
For the bouncing electrons from a metal surface is only needed light with specific frequency is called frequency or metal threshold energy. Each metal has a threshold energy is different and is a characteristic of these metals.
Strong currents grew with increasing frequency of light despite having the same intensity.
For example, the metal has a threshold frequency of the energy or green light, then when the green light on a metal surface, electrons will bounce or be no electric current. However, if used to use red or yellow light whose frequency is smaller than the green light, then no electrons that bounce off or not energized when the intensity of light used is greater than the green light.
If used light blue light whose frequency is greater than the green light then the electrons will bounce or no electric current and the remaining energy is converted into kinetic energy of electrons bouncing. The electric current generated electricity will increase if the intensity of blue light improved.
Also Read:
1. atomism
2. periodic system of elements
3. STABILITY IS BECAUSE ionic compound fulfilled the octet rule?
4. SOLUTION CONCENTRATION
* Albert Einstein High School CLASS II, Photoelectric Effect, photoelectric emission, light frequency, light intensity, Max Planck
THEORY OF ACID BASES LUX-FLOOD, SOLVENT SYSTEM AND USANOVICH
Leave a Comment Posted by Emel Seran on July 12, 2011
Note: Three acid-base theory are discussed in the article this was the quotation from the records and what is captured when kulia physical inorganic, so if there are any mistakes please leave a message in the comments box.
To understand more about the theory of acid-base please visit wikipedia in english here ...!!!
In addition to acid-base theory by Arhenius, Bronsted-Lowry and Lewis acid-base theory also known as the solvent system, acid-base theory lux-flood, acid-base theory usanovich acid.
Theory of Lux-Flood acid-base
Based on this theory of acids and bases in terms of donor and apsepto oxide ions. Acid chemical species that can menonorkan oxide ions (O2-), whereas a base species that can accept (oxide ion acceptors). This theory is commonly used to predict the reactions that take place at high temperature and metallurgical processes.
Examples of the reaction between CaO (lime) and SiO2 (sand), which occurs at high temperatures. Reaction equation as follows.
CaO (s) + SiO2 (s0 → CaSiO3 (s)
The reaction of CaO or SiO2 may also occur at lower temperatures according to the equation below.
SO3 (g) + H2O (l0 → H2SO4 (aq)
SiO2 (g) + H2O (l) → H2CO3 (aq)
Theory Basa acid solvent system
Acid-base system solvent system developed by Cady Esley. Based on this theory, acid solvent system which chemical species when dissolved in certain solvents can increase the concentration of the solvent cation characteristics.
The sample is dissolved in liquid NH3 NH4Cl, then acting as our NH4Cl acid solvent system as in NH3, NH4Cl fluids teriosisasi become NH4 + + Cl-. NH4 + cation is called solvent characteristics (CTF).
While alkaline solvent system which is a chemical species which, when dissolved in certain solvents can increase the anion plarut characteristics.
Examples of NaCl crystals dissolve in the liquid POCl2, then NaCl is called anionic solvent characteristics (AKP). Because of the mixture of NaCl decomposes into Na + and Cl-. Cl-is called the AKP.
So what if the solid KCl dissolved in liquid NH3?. If this is done then it is not including the theory of acid-base solvent system as KCl did not boost cation and anion solvent characteristics. In this case the solvent does not contain ions K + and Cl-KCl ionization yield.
Amino Acids Bases Theory Usanovich
Usanovich was a Russian chemist. Amino Acid Tongue Usanovich theory is not recognized by the world or practically no theory. This is due to the theory expressed a combination of all the theories that have been revealed acid-base experts other chemicals.
Russian chemistry is actually very advanced, but the chemistry book russia first (do not know now) almost all written in Russian so perkembagan chemistry russia is not much known to the people in the outside world. Note that in this world of chemical S1 graduates highly influential Russian and totally respected.
According Usanovich acid, which is a chemical species that can react with bases, may donate cations or anions and can accept electrons. While the base is a chemical species that can react with acids, can provide electrons or anions or cations can join.
Also Read:
1. Phosphorus Phosphorus Bombs And Dangers
2. WHITE GOLD, MINING, TYPE, ORE PROCESSING, PROPERTIES AND USE OF GOLD
3. One poison ricin feared in the world
4. these are the kinds of money that was, and is there now he Indonesia Beloved
5. transparent soap making mango seed
* High School CLASS II acid alkaline, acid-base and salt, acid base lewis, monoprotic acid, monoprotic acid and acid monoprotic, polyprotic acids, buffer, buffer, acid-base theory, acid-base theory arhenius, Theory Usanovich Acid Tongue Acid, acid-base theory lewis, acid-base theory Lux-Flood, solvent system theory Basa acid
FOOD DYES
Leave a Comment Posted by Emel Seran on June 1, 2011
Purpose of the dye
Purpose of food coloring so that food look more appealing and more refreshed, giving rise to taste the substance mencicipinya.Penggolongan pewrna
Based on the source pewrna dyes classified as natural and synthetic dyes.
For food dyes are classified by their solubility in water. Based on their solubility properties, grouped into food coloring dye and lake.
Dye is a common food dyes soluble in water. Dye is usually sold on the market in the form of powders, granules, pastes or liquids. Dyes are typically used for coloring carbonated beverages, soft drinks, bread, pastries, dairy products, sausage wrapper, and others.
clip_image002clip_image003
Picture Examples of synthetic food coloring dye
Lake is a combination of dyes and dye bases are covered by a specific substance. Because it is not soluble in water then this group of dyes suitable for dyeing products that should not be exposed to water or products containing fats and oils.
Substance Natural Dyes
Natural dyes are dyes (pigments) obtained from plant, animal, or mineral sources. Some dyes obtained from plants can be seen in the table.
Color
Source
Green Yellow
Brown
Red
Reddish yellow
Pandan leaves Turmeric
Fruit brown
Teak Leaves
Carrots
Here are explanations for some plants that can be used as a food coloring.
1. Fruit Bits (giver of pink or purplish red color)
Dark red fruit contains vitamin A (carotenoids), vitamin B1, B2, vitamin C and folic acid. Benefits include help treat liver disease and bile, penghamcur cancer cells and tumors, prevent anemia, lowers cholesterol and helps the production of red blood cells.
2. Carrots (giver of yellow / orange)
Carrots are beneficial in lowering cholesterol levels in the blood, and help defend the body from the risk of cancer, particularly lung cancer, cancers larynk (throat), esophagus (gullet), prostate, bladder, and cervix.
3. Turmeric (yellow poster)
Turmeric contains curcumin, a substance colored kuning.Jenis medicinal plant is useful as an anti-itch and anti-spasm, reduce swelling, and heal nasal congestion.
4. Cabbage (green color poster)
These vegetables are rich in protein, fat, carbohydrates, Ca, P, Fe, vitamin A, vitamin B and vitamin C. The benefit to relieve itching in patients with cough ditenggorokan, cure diseases of the head, head cleaning agents, cleaning agents blood, improves the kidney function, and improve and facilitate digestion.
5. Leaf Lettuce (green color poster)
Watercress leaves is also beneficial to health. In addition to fiber, light green vegetables also reduces the risk of cancer, cataracts, lower the risk of heart problems and stroke, reducing anemia disorder, relieve insomnia (sleeplessness), and helps the digestive and liver health.
6. Suji Pandan Leaves and Leaf (green color poster).
Suji leaves more often used as a dye on the cake snack market and pandan minuman.Daun can also give color to the dishes by grinding and squeezing the water, but the color is not as strong as the effect of Daum suji.
Types of substances giving color in natural dyes
In the natural dyes are certain substances that can give some color as well. Substances giving color to the natural dyes include: carotenoids, anthocyanins, Kurkum, biksin, caramel, titanium oxide, cochineal, carmine and acid karminat which will be discussed briefly.
1. Carotenoids
Carotenoids can be obtained from beets, carrots and papaya. Produces orange to red and is usually used to color products such as oil and grease cooking oil and margarine.
2. Anthocyanin
Includes red, orange, purple and blue crown found in many flowers and fruits. For example, roses, water henna, hibiscus, flower beads / kana, chrysanthemum, pelargonium, china aster, and apples, chery, grapes, strawberries, also found in the mangosteen fruit and sweet potato tubers. Telang flowers, produce purplish blue. Starfruit flowers produce red vegetable. The use of natural dyes, such as anthocyanin pigments are limited to some food products, such as beverage products (juice, juice and milk).
3. Curcumin
Produces yellow isolated from turmeric plants.
4. Chlorophyll
Includes green color in peoleh of green plants. For example, suji leaves and pandan leaves, the leaves are used as a producer katuk green color for different types of cakes traditional snacks. In addition to producing an attractive green color, the trio has a distinctive fragrance.
5. Biksin
Biksin give yellow like butter and is often used to color butter, margarine, corn oil, and salad dressings. Biksin obtained from the seeds of Bixa orellana tree located in the tropics
6. Caramel
Caramel with dark brown and is the result of the hydrolysis (breakdown) of carbohydrates, sugar, lactose and malt syrup. Caramel consists of three types, namely
a) caramel acid resistant. Often used for carbonated beverages.
b) liquid caramel for bread and biscuits
c) dry caramel.
Synthetic Dyes
Because the dyes are obtained from nature are very few color choices, then look for other alternatives to produce dyes and in the laboratory scale insdustri known as synthetic dyes. Synthetic dyestuffs found William Henry Perkins in 1856, but has been used since 1956 and there are currently approximately 90% of artificial dyes used in the food industry and in the laboratory.
The use of synthetic dyes have a maximum recommended levels, if used beyond the recommended maximum levels can interfere with health. But in a society prefer its use synthetic dyes. Here are some of the reasons more people have synthetic dyes.
a) more choice of colors and the price is cheap
b) are more durable and can produce strong colors in small amounts.
c) Colors generated from synthetic dyes will remain bright despite experiencing processing and heating.
Some limitations of natural dyes than synthetic dyes are as follows.
1. Often give taste or flavor characteristic undesirable.
2. Low pigment concentrations, requiring large amounts to produce strong colors or bright colors or interesting.
3. Low pigment stability.
4. Poor color uniformity.
5. Spectrum of color such as synthetic dyes.
6. Natural dyes readily degradable or fading when processed and stored. For example crackers who use natural dyes, the color will soon fade when subjected to the frying process.
Some dyes can produce the same color but different use. Dyes such as these are often misused by people either intentionally or accidentally. Please be aware that synthetic dyes were not for the food and beverage (textile dyes) can endanger health when entering the body because it is a carcinogen (causes cancer).
Some dyes belong to the class of natural dye but the dye was obtained through a chemical reaction or chemical means rather than by way of extraction and isolation. Types of dyes are produced by the chemical structure resembles the structure of natural dyes. Here are some dyes that are included in this type:
1. canthaxanthin (red)
2. apokaroten (red-orange)
3. beta carotene (orange-yellow)
Of the three dyes in the only beta-carotene use was not the limit, while the other two have a maximum concentration limits.
TYPES OF MATERIAL ON SYNTHETIC DYES MAKANANA
Beta Carotene
clip_image005Gambar structural formula of beta carotene
Naturally beta carotene found in carrots and is the giver of color substance in carrots. Beta carotene is one of the anti-oxidants found in fruits, such as found in carrots, potatoes and peaches. Very useful anti-oxidants to fight free radicals substances from toxic substances. Free radicals are the beginning of the disease, including heart disease here is so feared. With the anti-oxidant substances include beta carotene found in potatoes, carrots, peaches, etc., have been known to reduce by about 40%, with only consume 50 mg of beta carotene every day in her diet.
Typically, leafy dark green vegetables such as spinach, broccoli, sweet potato leaves contain lots of beta-carotene carrots danjuga. While fruits such as mango, avocado, watermelon and melon also contains a fair amount of these compounds.
Beta-carotene is a provitamin A true self that is an important source for vitamin A in the digestive tract especially in the small intestine, beta-carotene absorption will experience then stored in the liver cells. In the liver cells, beta-carotene is converted into vitamin A and is ready for use when needed for various metabolic reactions.
Besides beta-carotene is also expected to enhance the body's immune system against infection. How the mechanism and how big her role, still in further research. The ability of the antioxidant beta-carotene can also memeberikan protection against blindness, especially yng caused by cataracts. Cataract is pengeruhan the eyepiece, so the object becomes blurred shadow until it looks. Cataracts usually occurs with other aging diseases.
So many benefits of beta-carotene to support the health of the body. Nevertheless, it should also not consume excessive beta-carotene. Because whatever little excessive consumption of course there are many pengaruhnya.prinsip balance must hold onto the set menu harian.Tartrazin
Tartrazine (also known as E102 or FD & C Yellow 5) is a synthetic lemon yellow dye commonly used as a food coloring. Tartrazine is a derivative of coal tar, which is a mixture of phenolic compounds, polycyclic hydrocarbons and heterosklik. Because of their solubility in water, tartrazine dye commonly used as a beverage. Maximum absorbance of these compounds in the water falls at a wavelength of 427 ± 2 nm.
clip_image007
Image structure tarttrasin
Tartrazine is a dye commonly used in Africa, Sweden and Indonesia. To produce other colors, tartrazine can be mixed with E133 Brilliant Blue Brilliant Blue FCF or E142 Green Green S to produce a number of variations of the color green. European Parliament authorize the use of this compound in the EU country with the Decree of Council (Council Directive) 94/36/EC.
Although very Langkat, tartrazine can cause a number of allergic reactions and intolerance for people intolerant to aspirin or asthmatics. Aspirin or acetylsalicylic acid (aspirin) is a drug derived from salicylate compounds are often used as an analgesic (painkiller or minor aches), antipyretic (against fever), and anti-inflammatory (inflammation). Tartrazine allergy symptoms may occur when these compounds are inhaled (inhalation) or swallowed (ingestion). Allergic reactions that arise in the form of shortness of breath, dizziness, migraine, depression, blurred vision, and difficulty sleeping.
Here are some lists of foods that may contain tartrazine. Whether or not, more or less depending on the content of tartrazine manufacturing company policy or the chef making food. Soft drinks, puddings, chips, cereal, pastries, soups, sauces, ice cream, candies, jams, jellies, mustard, pickles, yogurt, noodles, and juice. While in medical products vitamins, antacids, capsules and certain prescription drugs.
FOOD DYES ARE PROHIBITED
Rhodamine B
Rhodamine B is a synthetic dye that should not be dipergunaan for food and have C28H31N2O3Cl molecular formula, molecular weight of 479,000. Rhodamine B is commonly used for coloring paper, and in the laboratory is used as a reagent for identification of Pb, Bi, Co, Au, Mg, and Th. Some physical properties of rhodamine B as follows:
1. green crystal or powder-reddish unggu
2. soluble in water will produce a bluish red color and strong berflourensi.
3. soluble in alcohol, HCl and NaOH.
Rhodamine B is now often used to color a variety of foods and beverages such as pastries, cakes, sauces, syrups, crackers. The characteristics of a food Rhodamine B is a striking bright red color. Usually a food coloring to color the food is not so bright red. The signs and symptoms of acute exposure to Rhodamine B is as follows.
1) If inhaled can cause irritation to the respiratory tract.
2) Contact with skin can cause irritation to the skin
3) If the eyes can cause irritation to the eyes, eye redness, edema of the eyelids.
4) If ingested can cause poisoning symptoms and urine red or pink.
5) If swallowed, may cause irritation of the digestive tract., And cause symptoms of poisoning and urine red or pink.
Actions that can be done when exposed to Rhodamine B
a. When exposed to the skin, remove the clothing jewelry, shoes sufferers contaminated / exposed Rhodamine B. Wash skin with soap and water to clean of Rhodamine B, for approximately 15 s / d 20 minutes, if necessary, contact your doctor.
b. When exposed to the eyes, rinse with running water or saline solution, eye-blink dikedip to ensure the rest of Rhodamine B is no more / cleaner, if necessary, contact your doctor.
c. If inhaled immediately pidahkan victims from the scene, attach mask berkatup or similar equipment to perform artificial respiration, if necessary, contact your doctor.
d. If swallowed and vomiting occurs, place the head lower than hips to prevent vomit into the respiratory tract.
e. If the victim is unconscious, tilt your head to the side or to one side, if necessary, contact your doctor.
Yellow Metanil
Is one of the substances that are not permitted color additives to be added to foods. It is used as color additives for textile products (clothing), wood paint, paint and paint. It is also commonly used as indicators of acid-base neutralization reactions.
FILE FOR THIS ARTICLE PLEASE DOWNLOAD HERE ...!!!!!!!
SUGGESTED ARTICLES:
1. Watch out for food additives (Code E)
2. INDEX BASED GROUPS WITH VARIOUS DYES chemical structure webside PLEASE OPEN THE FOLLOWING: http://stainsfile.info/StainsFile/dyes/dyes.htm OR CLICK HERE .....!!!!!
* High School CLASS II several types of synthetic dyes in the ingredients makanana, beta carotene, Chemistry, the types of food coloring, chemistry, organic chemistry, classification of food coloring. dye and lake, classification pewrna substances, natural and synthetic dyes, food coloring, dye uatan, rhodamine b, tartrazine, food additives
Colloidal systems
Leave a Comment Posted by Emel Seran on May 30, 2011
Preliminary
In everyday life we often intersect with colloidal system so it is important to assess. For example, almost all foodstuffs containing particles of colloidal size, such as proteins, carbohydrates, and fats. Emulsions such as milk also includes colloids. In the pharmaceutical field, most of the products are also in the form of colloids, such as creams and ointments which include emulsion. In the paint industry, cement, and rubber industry to make tires all involving colloidal systems. All forms such as spray for insects, paint, hair spray, and so on are also colloids. In agriculture, the soil can be classified as a colloid. So the colloidal system is very useful for human life.
Definition
Colloid is a mixture of circumstances form between the solution and suspension. The solution has the properties of homogeneous and stable. The suspension has a heterogeneous and unstable nature. While heterogeneous colloidal properties and stability.
Note the difference in the mix of the three examples below:
· A mixture of water with syrup
· A mixture of water and milk.
· A mixture of water with sand.
If we mix the water with the syrup syrup be dispersed (mixed) with water homogeneously (nodes) If ignored, the mixture does not separate and can not be separated by regular screening and filtering of soft (micro-filtration). Macroscopic and microscopic mcampuran looks homogeneous, indistinguishable where the water and where the syrup. Mix like this is called a solution.
If we mix the milk (eg, instant milk) with water, milk "late" but the "solution" was not clear but cloudy. If ignored, the mixture does not separate and can not be separated by filtration (filtering results remain murky). Macroscopic mixture looks homogenous. However, when observed with a microscope ultra was still distinguishable particles of milk fat dispersed in the water. Mix like this is called colloids.
If we mix the water with the sand the sand will be dispersed (mixed) with water and a direct split between heterogeneous water with sand, the situation will settle at the base of the sand and water can be separated by regular screening, and even can be separated by pouring slowly. Macroscopic mixture is already apparent hetrogen, where the water can be distinguished and what is sand. Mix like this is called a suspension.
In summary comparison of the nature of solutions, colloids and suspensions, as in Table beikut.
Nature
Solution
Colloid
Suspension
Size
1 nm
1-100 nm
> 100 nm
Pengyaringan
Filter / membrane
Filter
Not with a filter or membrane
Distance vision seemed
Does not appear
Looked with an electron microscope
Appear with a light microscope
Movement
Molecule
Brown
Gya weight
Running light
Transparent
Sometimes translucent / opaque
Often translucent frosted possible
Tyndall effect
There is no
There is
Number of phases
one
two
two
Colloidal system consists of two phases, the dispersed phase of a certain size in a dispersing medium. Substances called dispersed phase dispersed while while the medium used to disperse the medium is called dispersion. Size of the dispersed substances range from one nanometer (nm) to one micrometer (μm).
Example: starch and put in hot water it will form a dispersion system. Here the water as a dispersing medium, and starch as an agent dispersed.
So, quite a heterogeneous mixture of colloids (two-phase) and setabil. Substances called dispersible dispersed phase, while the medium used to disperse the substance called dispersion medium. Dispersed phase is discontinuous (intermittent), while the dispersion medium is continuous. In the milk mixture with water, the dispersed phase is fat, while the dispersion medium is water.
TYPES colloidal
Types of colloidal systems by type of dispersed phase and dispersion medium as shown in the table below.
No.
Substance dispersed
Medium dispersion
Name Type
Example
1.
Gas
Fluid
Foam
Whipped cream, beer foam, foam soap
2.
Gas
Solid
Solid foam
Pumice, foam rubber
3.
Fluid
Gas
Liquid Aerosol
Fog, clouds
4.
Fluid
Fluid
Emulsion
Mayonnaise, milk
5.
Fluid
Solid
Solid Emulsion
Cheese, butter
6.
Solid
Gas
Aerosol
Smoke, dust in the air
7.
Solid
Liquid
Sole
gel
Starch in water, jam
Gelatinous cold
8.
Solid
Solid
Sol solid
Black diamond, ruby glass
From the above table it can be seen that there is no colloid formed from a mixture of gases. This is due to a mixture of gases mixed evenly so that is also called a solution.
Aeresol
Aerosol there is a form of liquid aerosols and solid aerosols. Aerosols are liquid colloidal phase terdispersinya pendispersinya liquid and gas medium. Examples of liquid aerosol insecticides industrial output is in the form of spray, hair spray, and perfume. If sprayed in the air, liquid points will be spread in the air to form colloidal aerosols. Liquid aerosols occur naturally
For example, fog and clouds.
Fog is the points evenly dispersed in the air. Aerosols are solid colloidal phase terdispersinya pendispersinya medium solids and gases. Aerosol solid example of smoke and dust. Various smoke is actually a very fine solid partikelpartikel spread in the air. Noxious fumes that occur at home or in the room is smoke repellent and excessive smoke. Dust is also a solid particles are very fine, scattered in the air. Dust can be at home because of the wind from outside.
Foam
Foam was in the form of froth and foam solid. Froth or foam liquid colloidal phase is terdispersinya pendispersinya gas and liquid medium. The most common foam is foam soap. Another example is the beaten egg whites. Air as the dispersed phase and egg white as a dispersing medium.
In industry, there is substance to cosmetic hair spray foam in the form of liquid or foam. While in the food industry such as sample material for the liquid foam is creamy tart. Beige is packaged in a tube like toothpaste.
Solid foam, terdispersinya gas phase, medium pendispersinya solids. Solid foam products are widely used for packing fragile items or damaged is styrofoam. Styrofoam one example of a synthetic polymer.
Emulsion
Emulsions are colloidal phase pendispersinya terdispersinya and liquid medium, for example a mixture of oil and water. This mixture tends to separate so as to stabilize the mixture is usually added emulsifier.
The material is emulsion paint, toothpaste, cosmetic (cleansing milk, foundation), and salad dressings. Padasalad dressings to bring used oil and water emulsifier yolk. Soap is also an emulsifier to unite fats / oils on the body with water while cleaning the body. Terdispersinya dense emulsion phase liquids, solids pendispersinya medium. Examples of butter, cheese, and jelly.
PROPERTIES colloidal
Here are some of the topics that will be discussed on the properties of colloids.
a) Tyndall Effect
b) Brownian motion
c) Charge Colloids
d) Coagulation
e) Protective Colloid
f) Colloids and Colloid Liofil Liofob
a. Motion brown
Gerka brown or irregular motion is the random movement or zig-zag motion of colloidal particles. This is due to the impact of irregular daari premises colloidal particles dispersing medium. With the Brownian motion of colloidal particles is then protected from deposition due to constantly moving, so it becomes a stable colloid. Zig-zag motion of colloidal particles is called Brownian motion, named after its inventor Robert Brown a British biologist.
clip_image002clip_image004
Robert Brown and motion picture brwon.
If we observe under a microscope colloidal ultra, then we will see that the particles will move to form a zigzag. Zigzag movement is called Brownian motion. The particles of a substance constantly moving. The movement can be random as in liquids and gases (called motion brown), whereas in solids only beroszillasi in place (excluding motion brown).
For colloids with medium dispersing liquid or gas, the movement of the particles will produce collisions with colloidal particles themselves. The collision took place from all directions. Therefore, the particle size is small enough, then the collisions that occur tend to be balanced. So there is a resultant collision that caused a change of direction of motion of particles resulting in a zigzag motion or Brownian motion.
The smaller the size of the colloidal particles, the faster the Brownian motion that occurs. Similarly, the larger the size of the colloidal particles, the slower the Brownian motion that occurs. This explains why it is difficult Brownian motion observed in the solution and not found in a heterogeneous mixture of liquids with solids (suspension).
Brownian motion is also affected by temperature. The higher the temperature of the colloidal system, the greater the kinetic energy possessed pendispersinya medium particles. As a result, the Brownian motion of the particles phase terdispersinya faster. Vice versa, the lower the temperature of the colloidal system, the slower the Brownian motion.
b. Tyndall effect
Tindal effect is the effect of scattering of light by colloidal particles. Tyndall effect was discovered by John Tyndall (1820-1893), an English physicist. Therefore, it is nature called tyndall effect. Tyndall effect is an effect that occurs when a solution is exposed to light. At the time of the true solution (left picture) irradiated with light, the solution will not scatter light, whereas the colloidal system (picture right), the light will be scattered.
It happened because the Brownian particles have relatively large to scatter light. Instead, the true solution, the particles are relatively small so that the scattering that occurs only a few and very difficult to observe.
clip_image006
Pictures of scattering of light by water coconut milk (colloid) and colloidal solution of sugar which is not
Examples Tindal effect can be seen in the following two examples
clip_image008
Figure scattering of light by colloidal systems (left image)
Examples Tindal effect in daily life:
· If the sunlight coming through the gap into the room, they will be visible on light dust "flying (the area looks bright Leih).
· If koen clay films in theaters, then there ngrokok org. Keplaken ae wong iku pitch ... smoke that billowed upwards resulting light looks much brighter projector and the image on the screen becomes blurred.
· Highlight the headlights on a foggy night that more obvious, visible way tetapip unclear.
c. Adsorption
Adsorption of absorbance at the surface of colloidal particles by the force of adhesion of foreign substances. Power is very large due to the adsorption of colloidal surface of colloidal particles very wide when compared to the solid surface by the same amount.
Sol colloidal particles adsorbed ions are not always the same. It depends on the charge excess of medium pendispersinya. For example, if present in AgCl sol dispersing medium with excess Ag + cations, the AgCl will be positively charged. Whereas if AgCl contained in the dispersing medium by anion Cl-excess, it would negatively charged sol AgCl.
Different colloidal substances will adsorb differently. Adsorption properties of colloids is commonly used to adsorb / throw dirt / color and odor, separating the mixture, concentrating the ore, and other purification processes.
clip_image010
Figure uptake of a substance by substance adsorbent
Example: Colloidal Fe (OH) 3 because the surface absorbs positively charged H + ions. While colloidal As2S3 negatit charged because the surface absorbs ion S2. Look at the picture.
clip_image012
Absorption images on the surface of colloidal
Different adsorption absorption, absorption absorption that occurs in all parts. Adsorption properties of colloidal particles used in everyday life in the following processes.
· Water Purification
· Elimination of dirt pd syrup making process
· The process of eliminating body odor
· Pengguanaan activated charcoal d. Coagulation
Coagulation is the clotting of colloidal particles occurs due to damage to the stability of colloidal systems due to the incorporation of particles or a different charge sehinggas form colloidal particles even bigger. Coagulation can be done by mechanical and chemical:
· How mechanic: heating, cooling and stirring.
· How to chemicals: cross neutralizing or eliminating the charge and the addition of electrolytes.
Examples of processes that utilize coagulation properties of colloids:
a) rubber processing of raw materials (latex) with a coagulant such as formic acid.
b) Water treatment processes by adding alum. Alum aluminum sulfate (containing ions Al3 +) can be used to agglomerate slurry or sol colloidal clay in water (which are negatively charged).
c) If the soles of Fe (OH) 3 positively charged sol As2S3 plus negatively charged, it will happen coagulation.
clip_image014
d) The process of delta formation at the mouth of the river. Occurs because colloidal clay in river water had coagulation when mixed with electrolytes in seawater.
e) Smoke or dust can plant coagulated with electric coagulation instrument (airplane Cottrel). This method was developed by Frederick Cottrel (1877-1948).
f) The process is done by ion Al3 + or Fe3 + in neutralizing albuminoid particles contained in the blood, resulting in coagulation so as to cover luka.Pengolahan Water
Water treatment is based on the properties of colloids, ie coagulation and adsorption. River water or well water is murky sludge containing colloidal particles. There are also dyes, pollutants, such as sewage detergents, and pesticides. The materials needed for water treatment is usually aluminum sulfate alum, sand, chlorine or chlorine, calcium oxide, and activated carbon. Useful to crumple alum sludge to be more easily filtered. Tawas also form colloidal Al (OH) 3 can adsorb dyes or pollutant, such as detergents and pesticides.
If the treated water turbidity levels are too high, then the use of activated carbon in addition to alum. The sand serves as a filter. Serves as chlorine or chlorine disinfectant (disinfectant), while the calcium oxide is useful to raise the pH, which is to neutralize the acidity that occurs due to the use of alum.
Water treatment in big cities on the same principle with a simple water treatment described above. At first, the river water is pumped into a tub prasedimentasi. Here the sludge allowed to settle due to gravity. Disposed sludge pumps, while further water flowed into the tub Ventury. At this stage mixed alum and chlorine gas (preklorinasi).
In the raw water turbidity and high pollution, it is necessary affixed useful activated carbon to remove odor, color, taste, and organic substances contained in the raw water. From tubs Ventury, raw water that has been mixed with chemicals flowed into accelator. In the vessel coagulation accelator this happens, mud and other debris agglomerate to form floc-floc that will experience a gravitational sedimentation. Furthermore, the half-clean water flows into the tub sand filter. In this filter, the remaining flock will be captured. From the sandbox obtained water is almost clean.
The water is clean enough is accommodated in another tub called the siphon, where lime is added to raise the pH and chlorine gas (postklorinasi) to kill pests. From the air siphon, the water is clean water standards further flows into the reservoir, and then to the consumer.
Electrophoresis
Event is the event flow electrophoresis colloidal particles toward the electrode, the movement of colloidal particles into a single electrode showed that the colloidal particles are electrically charged. This phenomenon can be observed using cell electrophoresis apparatus as shown.
clip_image016
Electrolysis cell images
Colloidal dispersions U tube inserted into the mouth and then dipped electrode tube. If the wire is connected to the source of direct electric current and the electric current flowing through the positive and negative electrodes of colloidal particles will move to one of the electrodes. The particles are negatively charged colloidal dispersions will move towards the negatively charged electrode.
By using electrophoresis cell can be determined charge of colloidal particles. Electrophoresis can be used to separate the proteins in solution. Charge on the protein varies, depending on pH. By making certain pH (eg in buffer solution), separation of protein molecules of different types occur.
e. Protective Colloid
Protective colloid is a colloid protective colloid coagulation stop other experience that becomes more stable colloid. Protective colloid to form a layer around the colloidal particle to another. This layer protects the colloidal charge so that the colloidal particles are not easily settle or separate from the medium pendispersinya.
For example:
· In the manufacture of ice cream gelatin is used to prevent the formation of large ice crystals or sugar.
· Emulsifying agents (soaps and detergents).
· Fine granules in water stabilized with lecithin margarine.
· Carbon particles in the ink is protected with a solution of gum.
· The colors in the paint with the metal oxide stabilized by adding silicone oil.
· At the dairy, casein is used to protect the particles of oil or fat in a liquid medium.
f. Colloids and Colloid Liofil Liofob
Based on the nature of the adsorption of colloidal particles on pendispersinya medium, there are two kinds of colloids are: colloids and colloidal liofil liofob
· Colloidal liofil namely colloidal "liquid happy" (Greek: liyo = liquid; philia = happy). Colloidal particles will adsorb molecules of the liquid, forming a sheath around the colloidal particles that. Examples of colloidal liofil are starch, protein, and gelatin.
Characteristics Sol Liofil
1) Can be made directly by mixing the dispersed phase with medium terdispersinya
2) Having a small charge or uncharged
3) sol particles adsorb liofil pendispersinya medium. There is a process of solvation / hydration, the formation of an adsorbed layer of dispersant medium around the particles, causing the particles are not mutually joined sol liofil
4) The viscosity of the sol liofil> viscosity of the dispersing medium
5) Not easy to agglomerate with the addition of electrolytes
6) Reversible, meaning liofil sol dispersed phase can be separated by coagulation, can then be converted back into a sol with the addition of medium pendispersinya.
7) Provide a weak Tyndall effect
8) can migrate to the anode, cathode, or do not migrate at all.
· Colloidal colloidal liofob the "hate liquid" (phobia = hate). Colloidal particles do not adsorb the liquid molecules. Examples are colloidal sol liofob sulfide and metal soles.
The characteristics of Sol Liofob
1) It can not be made simply by mixing the dispersed phase and medium pendisperinya
2) Having a positive or negative
3) sol particles do not adsorb liofob pendispersinya medium. Particle charge obtained from adsorption particles are electrically charged ions
4) hydrophobic sol viscosity similar to the viscosity of the dispersing medium
5) Easy to clot by the addition of electrolytes because they have charge
6) means irreversible sol liofob have clumping can not be converted into sol
7) Provide a clear Tyndall effect
8) Will move to the anode or cathode, depending on the type of particle charge
STABILITY colloidal systems
Colloidal gas and most liquid colloidal precipitate in a very long time. This shows a stable colloid. Colloidal stability is due to Brownian motion. Although it has got to the bottom of the container, colloidal particles can go back up and keep moving in a medium. Other causes because most colloidal particles adsorb ions. The same colloidal particles adsorbed ions are similar, so that the colloidal particles repel each other because of the kind that has been adsorbed ions.
Colloidal particles are actually electrically charged (neutral). Events electrophoresis can be used to determine the type of charge on the ion adsorbed colloids. If colloids accumulate on the negative electrode, the positive ions adsorbed colloids have, and vice versa.
The stability of colloids can also be caused by adsorption of other molecules or colloids (colloidal protective / protective). For example, gelatin as a stabilizer of ice cream. Emulsions can be formed by the other colloids (emulsifier / emulsifier) as pengadsorpsi. For example, soap as emulsifier oil / grease and water.
Other emulsifiers such as casein in milk, and egg yolks in making mayonnaise. If the colloidal particles join together and collected into bigger particles, the colloids will terkoagulasi (clot) and will eventually settle.
In the chemical coagulation of colloidal particles can occur due to ions adsorbed colloidal particles has been stripped or neutralized. For example, by electrolysis or mixed electrolyte / ionic charge opposite. Another way is dicapur with other colloids adsorb ions have opposite charge. Ions will attract each other, bringing with them mengadsorpsinya colloidal particles. In physics colloid coagulation can occur due to heating or cooling. For example, an egg or coconut milk to coagulate when heated. Popsicles can be hard because cooled.
MAKING colloidal systems
There are two ways of making the means of condensation and colloidal dispersions way.
1. Condensation Method
Dual decomposition reaction.
For example:
1. colloidal As2S3 made in the style of H2S flow slowly through a cold solution of As2O3 As2S3 sol to form a bright yellow.
As2O3 (aq) + 3H2S (g) → As2O3 (colloidal) + 3H2O (l)
Negatively charged colloidal As2S3 because the surface absorbs ion S2
2. AgCl sol made by mixing a solution of AgNO3 solution and dilute HCl. Her reaction:
AgNO3 (ag) + HCl (aq) → AgCl (Colloid) + HNO3 (aq)
Redox reactions.
For example: gold sol or sol can be prepared by reduction of Au salt solution by dissolving organic AuCl3 in reducing formaldehyde HCOH. Reaction occurs:
2AuCl (aq) + HCOH (aq) + 3H2O (l) → 2AU (s) + HCOOH (aq) + 6HCl (aq)
While sulfur sol can be prepared by reduction of SO2 dissolved in water flowing H2S gas. Chemical reactions that occur:
2H2S (g) + SO2 (aq) → 3S (s) + 2H2O
Hydrolysis reaction.
Hydrolysis is the reaction of a substance with water. Misalanya: sol Fe (OH) 3 can be prepared by hydrolysis of FeCl3 solution by heating a solution of FeCl3 or Fe salt hydrolysis reaction in boiling water.
FeCl3 (aq) + 3H2O (l) → Fe (OH) 3 (colloidal) 3HCl + (aq)
(Colloidal Fe (OH) 3 because the surface absorbs positively charged ions H +).
Sol Al (OH) 3 can be obtained from the hydrolysis reaction of Al salt in boiling water.
AlCl3 (aq) + 3H2O (l) → Al (OH) 3 (colloidal) 3HCl + (aq)
Turnover reaction solvent
How this is done by replacing the dispersing medium that dispersed phase semulal arut after replacement pelarutanya be sized colloids. For example: to make a sulfur sol poorly soluble in water but soluble in alcohols such as ethanol with water dispersing medium, belarang must first dissolved in ethanol until saturated. Just then a solution of sulfur in ethanol is added slowly to the water while stirring. So the sulfur colloid will coagulate into particle due to lower sulfur solubility in water.
In contrast, calcium acetate soluble in ethanol, initially dissolved in water first, kemudianbaru added ethanol in the solution then condensation and formed colloidal calcium acetate.
2. How Dispersion
How Mechanic
Mechanical means is smoothing the coarse particles of solids with the milling process to form a colloidal-sized particles. The instrument used for this method called colloid mill, which is used in:
Ø The food industry to make fruit juice, jam, cream, ice cream, etc..
Ø household chemical industry to make toothpaste, shoe polish, detergents, etc..
Ø The chemical industry to make solid lubricants, paints and dyes.
Ø other industries such as plastic industry, pharmaceutical, textile, and paper.
How peptizing
How peptizing is manufacturing colloid / colloid system of coarse grains or from a sediment / sludge dispersing process with the help of a substance pemeptisasi (solver). Substance solver can be particularly electrolyte containing similar ions or certain solvents. Example:
Ø Gelatin dipeptisasi by water, rubber by gasoline
Ø Deposition NIS dipeptisasi by H2S, sediment Al (OH) 3 by AlCl3
Ø Sol Fe (OH) 3 obtained by stirring the precipitate Fe (OH) 3 are newly formed with little FeCl3. Sol Fe (OH) 3 then surrounded that positively charged Fe +3
Ø Some substances easily dispersed in certain solvents and colloidal systems membnetuk. For example: gelatin in water.
How to Bow Bredig
How Bredig bow is usually used to make the soles of metal, just as Ag, Au, and Pt. In this way, the metal is converted into particles kolid be used as an electrode. Then the two metals immersed in medium pendispersinya (cold distilled water) until both ends are close together. Then, the two electrodes will be stepping electricity, such as images.
clip_image018
Picture mode electric arc Bredig
Resulting heat will cause the metal to evaporate, the vapor will then be condensed in the cold dispersing medium, resulting in condensation in the form of particle-particle kolid. Because the metal is converted into particle kolid with metal steam process, then this method is considered as a method of dispersion.
Purification of Colloids
1) Dialysis
Dialysis is the separation of colloidal ions bullies in this way is called dialysis. That mixed with a fluid with colloid through a semipermeable membrane that serves as a filter. Semipermeable membrane can pass but can not be bypassed liquid colloids, so that the colloidal and liquid will be separated.
One of the dialysis process is the utilization of blood washing apparatus (Haemodialisis). In this process the bad blood from the patient is passed in pipes made of semipermeable membranes. Semipermeable pipe is drained fluid that serves as a washer (usually blood plasma), the ions in the blood stream will carry dirty blood plasma.
2) Ultra Filters
Kolid particles can not be filtered as regular paper filter, because the filter paper pores are too large compared to the size of the particles. However, if the filter paper is impregnated with cellulose such as cellophane, the pore size of paper will often be reduced. The modified filter paper is called ultra filter.
The purification process using ultra filters are slow, so the pressure should be increased to speed up this process. Lastly, particle-particle colloids will teringgal on filter paper. Kolid particles will be separated by size, by using ultra filter stages.
FILE colloidal systems PLEASE DOWNLOAD HERE ...!!!!!!
* High School CLASS II adsorption, adsorption, and liofil liofob, brown motion, Chemistry, colloid, colloidal, colloidal sol, colloidal systems, tyndall effect, electrophoresis, electrophoresis, motion brown, high school chemistry, chemistry, high school chemistry, colloid, colloidal sol , colloidal, and liofil liofob, Properties of Colloids, the properties of colloids, colloidal systems, Tyndall effect
pH and pOH (degree of acidity and alkalinity)
6 Comments Posted by Emel Seran on 21 April 2011
pH and pOH a solution of acids and bases as well as the method of determining pH and pOH a solution of acids and bases please download here ...!!!
* High School CLASS II, CHEMISTRY, Chemistry Questions and Discussion acidic, alkaline, acidic pH determination method, Chemistry, and alkalis, chemicals, solvents, acids and alkaline solutions, pH, acid pH, alkaline pH, pOH
valence electrons and electron difference last
Leave a Comment Posted by Emel Seran on March 1, 2011
In the electron configuration, the number of electrons present in the outer shell of an atom are called valence electrons. Most chemical bonds are formed by using electron valence electron valence that can be said to be a determinant of the chemical properties of an element. elements that have the same valence electrons will exhibit similar properties.
Last electron is an electron that is located in the subshell that has the greatest energy, the electrons are located on the last subshell according to Hund's rule.
Valence Electrons and Electron differences Newsletter
So the valence electrons of Cl is 7 and the last electron subshell Cl 3P5 lies in having blue arrows. have n = 3, = 1, m = 0, s = - ½
* High School CLASS II quantum number, the last electron, valence electrons, electron configuration, valence electrons and electron difference last
alcohol
Leave a Comment Posted by Emel Seran on 6 November 2010
Alcohol is an organic compound composed of atoms of organic C, H and O of the general formula CnH2n +1 OH. Characteristic is the presence alcohol-OH group on the carbon chain. Carbon chain alkyl groups can be saturated or unsaturated, substituted alkyl groups and can also be attached to the cyclic chains. In addition to the alcohol-OH group is also known that alcohol has-OH groups of more than one. Alcohol which has one-OH group called monohodroksi alcohol, alcohol with two-OH groups called dihydroxy alcohol and so on.
Based on carbon with-OH alcohol gugs grouped into:
a. Primary alcohol, the alcohol-OH group attached to C primary
clip_image002
b. Secondary alcohol, yairu alcohol-OH group attached to the secondary C
clip_image004
c. Tertiary alcohol, the alcohol-OH group attached to the tertiary C
clip_image006
Tata name Alcohol
IUPAC nomenclature
1) The nomenclature of alcohol is not so different from the name on alkanes. Suffix-a difference that is related to the alkane is replaced by the suffix-ol.
2) The number of the carbon atoms starting from the carbon atom closest to the-OH group.
Example
clip_image008
Tata Trivial Name
Tata trivial name or common name is only valid for low interest alcohols or alcohols with molecular formula is simple. Trivial nomenclature for the alcohol that is the name of the alkyl group which the-OH group followed by the word alcohol.
clip_image010
Isomers and the nature of Alcohol
The compounds of alcohol with the same number of carbon atoms can undergo isomer. Happened to alcohol isomer position, namely alcohol with the same number of carbon atoms but the location of the-OH groups in different structures. For example, alcohol with molecular formula C3H8O can be written with two structural formula
clip_image012
Solubility of alcohol in water is influenced by the number of carbon atoms contained in the alcohol. Alcohols with 1-3 carbon atoms meruapakan colorless liquid and soluble in water at any ratio, 4-5 carbon atoms slightly soluble in water while the alcohol the number of carbon atoms> 6 does not dissolve in water.
Based on the structure owned, alcohol is a mixture of alkanes or R and water. Cluster R are nonpolar or lipophilic-OH group is polar or hydrophobic, when alcohol by the number of carbon atoms slightly when dissolved in water then-OH groups can form hydrogen bonds with water molecules. However, when the number of carbon atoms more and more the nature of the R groups or nonpolar alkanes more dominant that the solubility in water insoluble reduced even when the number of carbon atoms increases.
The higher the molecular weight the higher the boiling point and viscosity. Boiling point of alcohol is higher than that of the alkane molecular weight almost the same as forming hydrogen bonds with other alcohol molecules. In alkanes do not form hydrogen bonds between the members of the molecules.
The boiling point of alcohol is a primary alcohol didh point> secondary alcohols> tertiary. In branched alcohols having a boiling point lower than the straight-chain alcohols. In terms have almost the same molecular weight or the number of carbon atoms. This disebabkaa alcohols branched shape of the molecule resembles a ball.
Alcohol functions
Here are some of the functions of alcohol in general
a) As a raw material synthesis of organic compounds
b) As a solvent
c) For the manufacture of synthetic detergents such as lauryl alcohol.
d) As the glass cleaner
e) For the animals are small collections of alcohol can be used as a preservative.
f) mixture of methanol and ethanol are blended with gasoline as fuel.
Reactions to Alcohol
-OH group is a functional group of alcohol and therefore most of the reactions occur in this cluster. Here are some of the reactions that occur in alcohol: the oxidation reaction, the replacement of the-OH group, the replacement of the H atom in the-OH group by acid groups, active metals and alkyl groups.
Oxidation
Alcohol with strong oxidizing agents such as H2SO4 + NA2Cr2O7 can undergo oxidation reactions. The results obtained from the oxidation reaction varies depending on the type of alcohol. Akohol primary if aldehyde is oxidized generating an excessive amount of oxidants will still continue memebntuk oxidation of carboxylic acids, secondary alcohols produce ketones whereas tertiary alcohols produce a mixture of carboxylic acids and ketones. The reaction between primary alcohols, secondary and tertiary NA2Cr2O7 + H2SO4 can be seen in the example.
clip_image014
Replacement of Cluster-OH
-OH group in the alcohol may be replaced by halogen atoms when reacted with phosphorus halides and acid halides. Phosphorus halides can be PX3 and PX5 while halogen acids HX form.
clip_image016
the rate of reaction of alcohol with a halogen acid is a tertiary alcohol> secondary alcohol> primary alcohol.
Replacement Atom H-OH by the Task Force Acid, Metal Cluster Active and Alkyl
clip_image018
Above reaction is a reaction between primary alcohols and carboxylic acids. When heated with the addition of a little concentrated sulfuric acid it will form an ester and H2O. H2O obtained from the above reaction of the alcohol formed from H and OH from acetic acid. When used tertiary alcohols derived from acetic acid H and OH of the alcohol.
If alcohol is reacted with inorganic acids derived products such as inorganic ester. Products obtained from the reaction of ethanol with sulfuric acid ethyl hydrogen sulfate and water, while the product obtained from the reaction of ethanol with nitrous acid ethyl nitrite and water.
clip_image020
H atom in the-OH may be replaced by an active metal such as Na. The reaction between the alcohol and the sodium salt Na produce alkoxide and the release of hydrogen gas. Salt obtained from this reaction when hydrolyzed will be recovered alcoholic origin. The rate of change of H atom by an active metal that is a primary alcohol> secondary alcohol> tertiary alcohol.
After the turn of the H atom by an active metal is reacted with an alkyl halide again will be the turn of the active metal by an alkyl group. Active metals are pushed out of the halogen reacts with alkyl halides to form salts.
clip_image022
Some Alcohol in Everyday Life
Methanol
Methanol or methyl alcohol is the first term of the alcohol with the molecular formula CH3OH. Methanol is toksit because it can cause blindness and death when exposed to the eye. Methanol in the form of a colorless liquid with a boiling point of 64.7 ° C, mass jeni 0.7918 g / cm ³,, easily soluble in water, volatile with a smell like alcohol plain and flammable. Spritus is a mixture of methanol and ethanol. Color additives on ethanol is not to drink.
Matanol produced mostly used as a base for the manufacture of manufacture formaldehit. Methanol is often mixed with gasoline, because the mixture could be expected to improve the quality of gasoline. However, methanol is added has a weakness because it can cause corrosion of some metals, including aluminum. These reactions occur in the combustion of methanol:
clip_image024
Methanol was originally obtained from the dry distillation of wood. Now methanol obtained by reacting carbon monoxide with hydrogen, with a catalyst ZnO + Cu. A mixture of CO and H2 gas heated to a temperature of about 450 º C with a pressure of 200 atm.
clip_image026
Ethanol
Ethanol is a type of alcohol consumed and has a boiling point and melting point respectively 78 º C and 114 º C. Ethanol has the formula C2H5OH and is often abbreviated as EtOH. Wine, beer and wiskey liquor containing a certain concentration of ethanol. Ethanol is a clear, colorless liquid, was burning in the mouth and throat if swallowed. Several types of beverages that contain alcohol are as follows:
- Group A: ethanol content of 1% - 5% (beer)
- Group B: ethanol content of 5% - 20% (wine)
- Group C: ethanol content of 20% - 45% (whiskey, vodka, manson house, johny walker, kamput)
Beverages such as wine and beer have been known known since prehistoric times. In those days munuman-beverage obtained from the fermentation of yeast or materials containing starch or sugar. As source material can be potato starch, cassava and rice. Generally materials containing starch can be processed into alcohol by fermentation or fermentation processes. Initially the starch-containing material soaked with water to form the enzyme amylase. Amylase enzyme that formed gradually decompose starch into glucose. With the help of zimase enzymes contained in yeast, glucose formed is decomposed into ethanol and carbon dioxide.
clip_image028
The fermentation process carried out at a temperature of 25 º C. At low temperature fermentation process is slow, while at high temperature the yeast is added will be killed. The concentration of ethanol derived from the fermentation process a maximum of 10-15%. This is due to the higher concentration of yeast cells killed so that the process of decomposition of glucose stalled.
To increase the alcohol obtained from the fermentation process is done by fractional distillation. The boiling point of ethanol is 78 º C and the boiling point of water 100 º C. From the fractional distillation process although very high concentrations of ethanol, but not obtained absolute ethanol. Of absolute ethanol is ethanol with a concentration of 100%. This is due to the ethanol and water form an azeotropic mixture so that only diperolehn ethanol with a purity of 96%. Azeotropic mixture is a mixture that has the same boiling point. To obtain absolute ethanol needs to be done by chemical means, namely by adding CaO or Mg (OCH3) 2 as a water towing.
In addition to ethanol by fermentation can also be produced hydration of ethylene using phosphoric acid catalyst at 300 º C.
clip_image030
In addition to the above can also be used indirectly hydration of ethylene with concentrated H2SO4. Hydration products obtained by hydrolysis to obtain ethanol.
clip_image032
Alcohol dihydroxy
Dihydroxy alcohol is alcohol in the molecule there are 2 pieces gugs-OH. Alcohols has two-OH groups called glycol. One example dihydroxy alcohol is ethylene glycol. Ethylene glycol following structural formula: clip_image034
Ethylene glycol is a colorless liquid with a sweet taste. Alcohol is well and dissolve in water.
Alcohol trihydroxy
Trihydroxy alcohol is alcohol, there are 3 pieces in the molecular-OH group. Glycerol or 1,2,3-propananatriol is one of the most important examples of the trihydroxy alcohol. The term comes from the Greek glycerol glykys which means sweet. Glycerol at room temperature in the form of a colorless viscous liquid with a sweet taste to the boiling point and melting point of 290 consecutive successive º C and 18 º C, it can be mixed with water and alcohol in all comparisons.
Glycerol in the laboratory is used as a solvent because it has absorbent properties of water (hygroscopic). In the field of industrial glycerol used as a perfume maker, lubricants, and used as an ingredient in cosmetics because glycerol is able to soften the skin.
Glycerol is generally made by means of hydraulic grease using NaOH and hydrolysis of 1,2,3-trikloropropana using K2CO3 and H2O.
clip_image036
* High School CLASS II, Carbon And Senyawaannya ALCOHOL, dihydroxy Alcohol, Alcohol primary, secondary alcohols, tertiary alcohols, trihydroxy alcohol, some alcohol in Everyday Life, How to Distinguish Alcohol Ether, How to Differentiate Primary Alcohol, How to Distinguish group Alcohol Group Phenol, Chemistry, Ethanol, absolute ethanol, Function Alcohol, Glycerol, isomers and nature of alcohol, carbon and senyawaanya, chemistry, Methanol Oxidation, Reaction to Alcohol trihydroxy, Reactions on Alcohol, Secondary, Secondary and Tertiary, Alcohol Nomenclature, IUPAC nomenclature, nomenclature trivial or common name, Tertiary with Phenol, wanibesak
SOLUTION CONCENTRATION
5 Comments Posted by Emel Seran on 5 November 2010
The solution is called a homogeneous mixture. Called the mixture because the arrangement is subject to change and are called homogeneous composition is so uniform that the boundary between the dissolved substances and solvents can not be distinguished even though the optical microscope. Homogeneous mixtures of gas, gold and bronze can be said as well as the solution. But the solution is usually the term used for the liquid phase.
Substances that have the solid phase and the gas is typically referred to as the solute (solute) while the liquid berfasa said to be solvent. A substance is said to be solvent if it has a larger number than the number of solute. Under certain conditions such as a mixture of alcohol and water in the ratio 50:50. Of the mixture is a little dubious to determine which acts as a solvent and which bertimdak as solute. Such a mixture of water and alcohol can be considered as a solvent and can also be regarded as the solute. Another case in making syrup. In the manufacture of sugar syrup more than the amount of water but the water is still regarded as solvent as it can maintain his physical condition while sugar or sucrose is called the solute.
To state the amount or more substances dissolved in a solution concentration used term. There are several methods used to express the concentration of solute in solution.
1. Mass percent
clip_image002
Example
a. How many% sugar solution made by dissolving 10 g of sugar in 70 g of water.
clip_image004
b. How many grams of sugar contained in 500 grams of 12% of the mass of the sugar solution.
clip_image006
2. Percent volume
clip_image008
The concentration of a solution of two liquids is expressed as a presentation volume. It is usually found at a concentration of alcohol. For example vodka containing 15 percent alcohol in 100 ml of vodka means there are 15 mL of alcohol.
For example, specify% alcohol volume of a mixture. 40 mL of alcohol mixed with 50 mL of acetone then:
clip_image010
3. ppm and ppb
For very dilute solutions the concentration used to express units of parts per million or parts perjuta (ppm) and parts per billion or parts per billion (ppb).
clip_image012
solution with a concentration of 1 ppm means containing 1 gram of solute in every 1 million grams of solution or 1 mg of solute in every 1 kg of solution.
clip_image014
Due to a very dilute solution has a density of = 1 g / mL, then 1 ppm is defined as 1 milligram of solute in 1 liter of solution.
clip_image016
4. Molality
Kemolalan state the number of moles of solute in 1 kg of solvent.
clip_image018
clip_image020
clip_image022
clip_image024
With, Mr = molar mass, P = weight of solvent (g)
Example
1) What is the molal NaCl solution if known mass percent NaCl = 10%
Answer
clip_image026
2) What is the molality solution made by dissolving 3 g of urea (CO (NH) 2) 2) in 500 g of water? (Mr urea = 60)
Answer
clip_image028
5. Molarity (M)
Molarity stated number of moles of solute in 1 liter of solution or the number of millimoles of solute in 1 mL of solution.
clip_image030
Solution of 0.50 M means 0.50 moles of substance in one liter of solution or 0.50 millimoles of substance in 1 mL of solution.
clip_image032
clip_image034
1L = 1 dm3 = 1000 mL = 1000 cm3
1 mole = 1000 mmol
Example
If in a reagent bottle contained 250 mL of NaOH solution contained (Mr = 40) concentration of 0.4 M. then
a. How many moles of NaOH are contained in the solution
b. How many grams of NaOH are dissolved in the solution
Answer
a. Solution volume = 250 mL = 0.25 L
Moles of NaOH were dissolved = 0.25 L x 0.4 mol / L = 0.10 mol
b. Grams of NaOH are dissolved in a solution of NaOH = mol x Mr NaOH
= 0.1 mol x 40 g / mol = 4 g
% Solution molarity relationship with mass
clip_image036
clip_image038
clip_image040
Available in the laboratory formic acid solution (CHO2H) 4.6%. (Ar H = 1, C = 12 and O = 16) with a density of 1.01 g / mL. Determine the concentration of the solution ...
Answer
clip_image042
Or
v Mass solution = 1000 mL x 1.01 g / mL = 1010 g
v =% mass of solute mass of solution = mass x 4.6 / 100 x 1010 g = 46.46 g
v Mol CHO2H dissolved in 1 liter of solution = 46.46 g/46 g / mol = 1.01 mol
6. Mole fraction (X)
Stating the number of moles mole fraction of solute or the number of moles of solvent in the total number of moles of the solution.
clip_image044
clip_image046
clip_image048
Example
1) In a solution of 16% of the mass of naphthalene in benzene, determine the mole fraction of each substance, if known Mr naphthalene = 128 and Mr benzene = 78?
Suppose the total solution = 100 g
clip_image050
clip_image052
clip_image054
clip_image056
clip_image058
clip_image060
Mol fraction relationship, Kemolalan and Kemolaran
Konstrasi solution can dikonfersikan from unit to unit lain.misalnya a 40% NaNO3 solution of density 1.36 g / mL. Calculate the mole fraction, and kemolaran kemolalan of NaNO3? (Mr = 85)
Answer
Mass solution = 1000 mL x density of
= 1000 mL x 1.36 g / mL
= 1360 grams
NaNO3 were dissolved in 1 liter of solution
clip_image062
Molar mass NaNO3 = 85 g / mol
clip_image064
The amount of water in the solution
= Mass of solution - mass of NaNO3
= (1360-544) g = 816 g
= 816/18 = 45.33 mol
a. Mole fraction of NaNO3
clip_image066
clip_image068
clip_image070
Mole fraction of H2O
clip_image072
clip_image074
clip_image076
b. Kemolalan
clip_image078
clip_image080
c. Kemolaran
clip_image082
clip_image084
* High School CLASS II ppm, Chemistry, mole fraction, mole fraction relationship with kemolalan and kemolaran, relationships% molarity solution with mass, chemical, solution concentration, solvent, malalitas, mass molar, molal, molar, molarity, solvents, percent by mass, percent volume, ppb, ppm, ppm and ppb, wanibesak, solutes
Electron KonfigurasiÂ
Leave a Comment Posted by Emel Seran on 1 November 2010
Technorati Tags: electron configuration, Aufbau rules, principles and rules ban pauli hund, orbital shape write electron configuration orbital, the electron configuration for the ion, subkulir spd and f, the energy level diagram
The electron configuration is a way of writing that shows the distribution of electrons in the atomic orbitals. Writing electron configurations follow some rules are rules Aufbau, Pauli principle and Hund's rule prohibition. Each orbital in each subshell is occupied by a maximum of two electrons, namely:
Ø subshell s made of 1 s orbital and occupied by two electrons
Ø Sub leather made from 3 p and p orbitals are occupied by 6 electrons
Ø d subshell made of 5 d orbitals and occupied by 10 electrons
Ø f subshell is made of 7 f orbitals and occupied by 14 electrons
F subshell because only up until now the electron configuration for the element with the highest atomic number just to f subshell.
Aufbau rules
The term comes from the German Aufbau meaning to build or increase. This rule states that electrons in the orbital filling always starts from orbital which has a low energy level to the orbitals that have a higher energy level. This rule was made so that the atoms are at their minimum energy so as to achieve stable. Energy-level diagram according to Aufbau rules:
clip_image005
Based on the energy level diagram above, the Aufbau filling order of electrons is as follows: 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p.
Prohibition Pauli principle
Pauli principle prohibition proposed by Wolfgang Pauli, it is in one atom, there can be no two electrons have the same four quantum numbers. The purpose is two electrons occupy an orbital electrons. In 1 atom principal quantum number, azimuthal quantum number and the magnetic quantum numbers are the same, the different is the spin quantum number. For example, the 1s orbital occupied by two electrons.
First electron: n = 1; l = 0; m = 0; s = + ½
Second electron: n = 1; l = 0; m = 0; s = - ½
Based on the principle of prohibition Pauli, each atom has one electron in the first set of quantum numbers (n, l, m, s) specific. 4th quantum number specifies the region in space where an electron is most likely to be.
n = indicates the atomic shell.
l = show subkulitnya.
m = indicates orbital
s = show spin.
Hund's rule
If there are orbitals with the same energy, each filled with one electron orbitals first (half full) with the same spin. If there are still some remaining electrons then the electrons are added at each orbital with opposite spin to spin early. For example, filling electrons in orbitals of oxygen.
Electron configuration 1s2 2s2 2P4 = 8o
Orbital diagram: clip_image009 clip_image011clip_image013
Writing Electron Configurations
Electron configuration can be written based on the order of Aufbau or may be abbreviated using the noble gas electron configuration. Abbreviation is done so that the writing is not very long electron configurations besides the formation of chemical bonds act more valence electrons, while the electrons closer to the nucleus is not so influential in the formation of chemical bonds.
For example:
10Ne = 1s2 2s2 2P6
11Na = 1s2 2s2 2P6 3S1 or (Ne) 3S1
Ion electron configuration
charged y + cations are formed when neutral atoms shed electrons y. Electrons are released are the electrons of the outer shell.
21Sc = (Ar) 3d1 4S2
Sc3 + = (Ne) 2s2 2P6
26Fe = (Ar) 3d6 4S2
Fe2 + = (Ar) 3d6
Fe3 + = (Ar) 3d5
Y-charged anion formed from neutral atoms by absorbing electrons y. Electrons are absorbed it into the orbital with the lowest energy level that has not been filled.
17Cl = (Ne) 3P5 3S2
17Cl-= (Ne) 3P6 3S2
Orbital Shape
1) Orbital s
The shape of the spherically symmetric and has only one kind of orbital. The greater the value of n, the size also increases.
clip_image015
2) Orbital p
Orbital numbering 3 pieces located in subshell p. All three have the same energy, but the direction of the space / different orientation (includes = px, py and pz). Each orbital is shaped like a twisted balloon is described using the Cartesian coordinate axes x, y and z.
clip_image017
3) Orbital d
Orbital is situated in the subshell d and consists of five kinds (including = DXY, DXZ, dyz, dx2 - y2, dz2). Orbital shapes can be described as 4 pieces of balloons twisted in Cartesian coordinates.
clip_image019
clip_image021
Description:
DXY = orbital lobe-lobe lies between the x axis and y
Orbital DXZ = lobe-lobe lies between the x axis and z
= Dyz orbital lobe-lobe lies between y and z axis
Orbital dx2 - y2 = lobe-lobe lies on the x axis and y
Orbital dz2 = consists of 1 twisted balloon located on the z axis and 1 area
donut-shaped lies in the xy plane
Tags :
0 komentar
Post a Comment