Question

In the electrolysis of water,why is the volume of gas collected over one electrode is double than the gas collected over the other electrode?​

Answer 1

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$\large\underline{\underline{\red{\sf Question}}}$

In the electrolysis of water,why is the volume of gas collected over one electrode is double than the gas collected over the other electrode?

$\large\underline{\underline{\red{\sf Required\; Answer}}}$

We know that water is made up of Hydrogen and oxygen . And the Molecular formula of water is $\sf H_2O$ . From the Molecular formula we can see that two Atoms of Hydrogen combine with one molecule of oxygen to form water . hence the number of hydrogen atoms is doubled than the number of oxygen atoms.when electricity is passed through water water break down into to hydrogen and oxygen .

$\boxed{\red{\bf \underset{\blue{Water}}{2H_2O(l)}\xrightarrow{\green{Decomposition}}\underset{\blue{Hydrogen}}{2H_2(g)}+\underset{\blue{Oxygen}}{O_2(g)}}}$

Hence , we can see that water splits in to two molecules of hydrogen and one molecule of oxygen. Since, number of molecules of hydrogen released is double the number of molecules of oxygen released , therefore the volume occupied by hydrogen gas is double the volume occupied by oxygen gas.

So , In the electrolysis of water, the volume of gas collected over one electrode is double than the gas collected over the other electrode.

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$\large\underline{\underline{\red{\sf Electrolysis \;of \;water :-}}}$

in the decomposition of water into Oxygen and hydrogen when an electric current is passed through water containing a few drops of dilute sulphuric acid.

Apparatus Required :-

Take a plastic mall drill two holes at its base and fit rubber stoppers . In this holes insert carbon electrodes to a battery and fill the mug with water such that the electrodes are immersed in it . Add a few drops of dilute sulphuric acid to the water .

Take to test tubes filled with water and invert them over the two carbon electrodes .Switch on the current and leave the apparatus undisturb for sometime.

We will observe the formation of bubbles at both the electrodes .We will see that the volume of gas collected at both the test tube is not same. Hydrogen gas and Oxygen gas are liberated in the ratio 2 : 1.

$\textsf{\textbf{\purple{\qquad\qquad\red{ \dashrightarrow }\: Diagram \;of\:Apparatus:-}}}$

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Answer 2

Answer:

Water composition is 2atoms of H and 1atom of O . Therefore H is double than O . The two electrodes collect H and O separately . We know that hydrogen composition in water is double than oxygen , so we find volume of gas collected in one electrode is double than volume of gas collected in another electrade .

hope it helps you....