Question

Water contains 88.89% of A by weight is decomposed into its elements B and oxygen. Pure C is a poor conductor of electricity and hence it is acidified using dilute sulphuric acid. When an electric current is passed through acidulated water, using platinum electrons, hydrogen gas is evolved at cathode and oxygen gas is evolved at D.

What is A?

• A. Oxygen
• B. Hydrogen
• C. Water
• D. Sulphuric acid

Answer 1

The correct option is A Oxygen

Percentage of oxygen in water

$=\frac{weightofoxygeninwater}{weightofwater}\times 100$

$=\frac{16}{18}\times 100$

$=$ 88.89%

Thus, water contains 88.89% of oxygen (A).