Question

during electrolysis of water the amount of gas collected in one test tube is double the amount collected in the other

Answer 1

it is because the formula of water is H2O. when the electrolysis happened the compound get break down into molecule and atom  i.e, 2 atoms of h and 1 atom of o, therefore the amount of hydrogen is  doubled than oxygen because hydrogen has 2 atoms 

Answer 2

Answer:

This happens because water is a compound which is made up of two parts / molecules of hydrogen and one part of oxygen. (H2O)

Hope it helps....

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