Oxygen has two allotropes: oxygen (O2) and ozone (O3). Allotrope is a different behavior shown by a substance whose constituent atoms, atoms of the same element, but there are differences in the amount and manner differences terikatanya constituent atoms. In this laboratory ozone produced by giving an electric charge in pure oxygen. Unlike other molecules, although ozone prepared by the same atoms but are polar. Other molecules such as O2, H2 and P4 are nonpolar because the molecule is nonpolar. Ozone protects the earth from the sun, but now realize that the ozone layer has thinned due to the release of activists due to substances that are harmful to the ozone layer increases.
Oxidizing one of the most prevalent and powerful in laboratories, industry and in our daily lives is the oxygen molecule, O2. Dioxygen (O2) gas is colorless and odorless occupy 21% air. Because the oxygen atom is also a major component of water and rocks, oxygen is the most abundant element in the earth's crust.
Joining oxygen through a chemical reaction of a substance commonly referred to as oxidation. Although this view has been abandoned, but the reactions involving oxygen substances that oxidize easily determined. Withdrawal of oxygen from a substance is called reduction. A substance composed of oxygen with certain elements are called oxides. Oxide divided into
1. metal oxide
2. oxides of non-metals
3. amphoteric oxide
4. oxide neutral
5. superoxide
Oxygen Reaction with Metals
The formation of metal oxide occurs by direct reaction between the metal with oxygen to form metal oxides often called corrosion. Metal oxide called alkaline oxides as reaction with water gives an alkaline solution (pH> 7).
Indeed, the formation of oxides in the form of corrosion is something that is troublesome and economical sources of waste in the community. Iron reacts with oxygen in the presence of water vapor to form rust, which is a crystalline iron oxide containing water molecules in a specific quantity.
2Fe (s) + 2/2O2 (g) + xH2O (g) → Fe2O3.xH2O (s)
Aluminium merupakanlogam other metals are usually widely known also form oxides by direct reaction with oxygen in the air.
2AL (s) + 2/2O2 (g) → Al2O3 (s)
Aluminum reacts with oxygen more easily than different besi.namun iron. Aluminum oxide on aluminum formed strongly attached to the surface of the metal so that it effectively protects the metal from further oxygen attack. Because of this disunakan aluminum as a metal building.
The reaction between iron and aluminum with iron, including slow. But sometimes a reaction between a metal with oxygen can quickly take and release large amounts of heat and light. The reaction with oxygen is usually called combustion. An example is the burning magnesium.
2mg (s) + O2 (g) → 2MgO (s)
Although iron corrosion occurred slowly, the iron can be made to react quickly by raising the temperature and increasing the concentration of O2. For example, cutting steel with acetylene flame initially implemented the steel heats to high temperatures with oxygen-acetylene flame. After the metal was very hot, acetylene gas flow is turned off and the hot steel is sprayed continue using pure oxygen flow. In this process a large amount of heat released can melelhkan steel and dust and sparks will crack everywhere.
The reaction of oxygen with non-metals
Oxygen also reacts with elements forming oxides nologam nanlogam covalently bonded. Often referred to as non-metallic oxide oxide base because its reaction with water causes the solution to become acidic (pH <7).
Examples are sure you know the O2 reaction with carbon in the form of charcoal or coal briquette. With the presence of excess O2 obtained product was carbon dioxide, but if the limited supply of oxygen will form a karbonmonooksida.
C (s) + O2 (g) → CO2 (g)
C (s) + O2 (g) → 2CO (g)
Carbon monoxide itself can react with oxygen to form CO2
2CO (g) + O2 (g) → 2CO2 (g)
This reaction is highly exothermic (DH =-284kJ per mol) and CO is used in industry as a fuel because it can be made easily from coal and easily sent through the pipe. Solid carbon dioxide is called dry ice is used for smoke effects.
Two non-metallic element that readily reacts with the sulfur and phosphorus oksigern. Sulfur burns in air with a blue flame and produces sulfur dioxide gas which is a suffocating gas stimuli.
S (s) + O2 (g) → SO2 (g)
Consists of two allotropes of phosphorus are white phosphorus and red phosphorus. Both burned dioxygen produces P4O10. However, it should be because white phosphorus spontaneously reacts with oxygen.
P4 (s) + O2 (g) → P4O10 (s)
Not all non-metals can react with metal. For example, nitrogen. This has led to a mixture of nitrogen and oxygen in the atmosphere is stable.
Attempts to ignite a mixture of N2 and O2 are not successful because they occurred by endothermic reaction. But if the air is heated at very high temperatures such as in a car engine, produced small amounts of NO. When released into the atmosphere through kanlpot compounds initiate the chain reaction eventually produces smoke haze.
amphoteric oxide
Oxide formed by amphoteric elements (B, Si, As, Sb, Te, Po) is called a amphoteric oxide. Called amphoteric because it can act as an acid and can also act as a base depending on conditions or larutn reacted to him.
In stronger acid amphoteric oxide acts as a base, so instead reacted with a more alkaline substances act as acids amphoteric oxide.
In stronger acid amphoteric oxide acts as a base, so instead reacted with a more alkaline substances act as acids amphoteric oxide.
Oxide Oxide Neutral or indifferent
Oxide is an oxide that is not neutral acidic and alkaline when dissolved in water, such as CO, N2O and MnO2.
peroxide
Peroxide is an excess of oxygen in the compound or group of compounds containing oxygen-oxygen bond in its molecular structure.
For example, hydrogen peroxide (H2O2) which is used as a bleaching agent and disinfectant as a result of the reaction in the form of H2O and oxygen. Pure H2O2 is a pale blue liquid is more viscous than water, the freezing point is unstable -0.46 ° C. In the laboratory hydrogen peroxide obtained from the reaction of barium peroxide with cold dilute sulfuric acid.
BaO2 (s) + H2SO4 (aq) → BaSO4 (s) + H2O2 (aq)
superoxide
Superoxide same thing as the peroxide oxygen-oxygen bond has. But in superoxide, occurs more than one excess oxygen while excess superoxide occurs only 1 atom of oxygen. Oskida-alkali oxides directly obtained from the reaction between the metal elements with oxygen at high temperature and pressure. One example of superoxide is K2O.
K2O typically used to restore the people who poisoned gas. In addition it is also used in submarines, to remove the carbon dioxide gas and water vapor resulting from the breathing of the crew. Terjaid reaction between KO2 with water vapor and carbon dioxide as follows.
K2O (s) + 2H2O (g) → 4KOH (s) + 3O2 (g)
KOH (s) + CO2 (g) → KHCO3 (s)
From the reaction of oxygen gas is inhaled will soon be replaced by O2 generated from the reaction between water vapor K2O.
Oxygen Reactions with Organic Compounds
Organic compounds are generally regarded as carbon compounds. Nevertheless, some compounds such as CO2 and CaCO3 although containing carbon atoms in the molecule are considered as inorganic compounds.
The simplest organic compounds called hydrocarbons. That is a compound composed only of carbon and simple hidrogen.hidrokarbon is methane, CH4, which is the main component of natural gas. Hydrocarbons are also a constituent of gasoline, kerosene, diesel and wax.
Methane and other flammable hydrocarbons in the air. If there is enough oxygen combustion products are carbon dioxide and water vapor.
CH4 (g) + O2 (g) → CO2 (g) + 2H2O (g)
If oxygen is available in small amounts of carbon monoxide and combustion products in the form of water vapor.
2CH4 (g) + O2 (g) → 2CO (g) + H2O (g)
If oxygen is available only little hydrogen to form water vapor and carbon berupanyala berjegala that contain the element carbon.
CH4 (g) + O2 (g) → C (s) + 2H2O (g)
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