Question

A balloon filled with___ gas rises in the air because the density of___ gas is less as compared to air.

• A. hydrogen
• B. hydrogen

Answer 1

1. The molecular weight of hydrogen gas is 2.
2. The molecular weight of oxygen present in the air is 32.
3. So, hydrogen gas is very light as compared to air.
4. Hence, the density of hydrogen gas will also be less than the density of air.
5. So, the hydrogen gas will move upward due to its lightweight.

Hence, a balloon filled with hydrogen gas rises in the air because the density of hydrogen is less compared to air.