Why is the amount of gas collected in one of the test tubes in text book Activity 1.7 (i.e., electrolysis of water) double of the amount collected in the other? Name this gas.

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Chapter 1

NCERT

Class 10

Science

Solutions

2. Why is the amount of gas collected in one of the test tubes in text book Activity 1.7 (i.e., electrolysis of water) double of the amount collected in the other

Question:

Why is the amount of gas collected in one of the test tubes in text book Activity 1.7 (i.e., electrolysis of water) double of the amount collected in the other? Name this gas.

Answer:

Since water is made up of two hydrogen atoms and one oxygen atom, the amount of gas collected in one test tube is twice that of the other. The name of the first gas is hydrogen gas and the name of the second gas is oxygen gas.

A decomposition reaction is the exact opposite of a combination reaction. As hydrogen reacts with oxygen to form water and an electric current is passed through water, the electrolysis of water produces hydrogen and oxygen.

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