Describe a method of preparing oxygen without using a source of heat. mention a test of oxygen.
In long plz i want is fast.

Dear Student 

Preparation of oxygen without the use of heat is by electrolysis of water: 

The electrolysis of acidified water is carried out in a Hoffmann Voltameter. Oxygen is evolved at the positive electrode in the electrolysis.

2H2O    2H2 + O2

A solution of barium hydroxide with nickel electrodes may also be used. However, on prolonged electrolysis an explosive mixture of oxygen and hydrogen may be evolved at the positive electrode.

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Because oxygen is a component of air, it has been studies extensively over the centuries and there is a large number of different methods for its preparation.

The most convenient method for preparing oxygen in the laboratory involves either the catalytic decomposition of solid potassium chlorate or the catalytic decomposition of hydrogen peroxide.

Preparation of oxygen Using potassium chlorate

Potassium chlorate decomposes at a low temperature if previously mixed with manganese dioxide which is a catalyst for the decomposition. Only the potassium chlorate is decomposed, and no perchlorate is formed :

2 KClO3   ==>   2 KCl  +  3 O2

Preparation of oxygen using hydrogen peroxide

The decomposition of hydrogen peroxide using manganese dioxide as a catalyst also results in the production of oxygen gas.

2 H2O2   ==>   2 H2O   +   O2

Preparation of oxygen by electrolysis of water

The electrolysis of acidified water is carried out in a Hofmann Voltameter. Oxygen is evolved at the positive electrode in the electrolysis.

2 H2O   ==>   2 H2   +   O2

A solution of barium hydroxide with nickel electrodes may also be used. However, on prolonged electrolysis an explosive mixture of oxygen and hydrogen may be evolved at the positive electrode.watch General Methods of Preparation of Oxygen to learn more.

Preparation of oxygen by the chemical decomposition of water

Oxygen is obtained from water by passing a mixture of steam and chlorine through a strongly heated silica tube containing pieces of broken porcelain.

2 H2O   +   2 Cl2   ==>   4 HCl   +   O2

The hydrogen chloride is removed by a wash-bottle containing sodium hydroxide solution and the Oxygen collected over water.

Preparation of oxygen By decomposition of oxides

Oxygen may be obtained by heating some metallic oxides.

When mercuric oxide is strongly heated in a hard glass tube, it decomposes, globules of mercury collect in the cooler part of the tube and oxygen gas is evolved. It may be collected over mercury in a pure and dry state.

2 HgO   ==>   2 Hg   +   O2

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