7.What is the reason that despite being third most abundant element on the Earth’s surface and most abundant chemical substance in the universe, Hydrogen is not found as a gas in Earth’s atmosphere? [A] It is very reactive and unstable gas [B] It is so light that readily escapes earth’s gravity [C] It is not found in free state in nature [D] None of the above reasons Show Answer
Notes: Under ordinary conditions on Earth, elemental hydrogen exists as the diatomic gas, H2. However, hydrogen gas is very rare in the Earth's atmosphere (1 ppm by volume) because of its light weight, which enables it to escape from Earth's gravity more easily than heavier gases.
