Why is there virtually no hydrogen and helium present in the atmosphere today?
A)These gases were burned off by solar radiation.
B)The gravitational force of Earth was not strong enough to hold them.
C)These gases were consumed by rock-forming processes.
D)Acid rain removed these gases from the atmosphere.

Question

Quizplus · Accepted Answer

Hydrogen and helium are both light gases, which means they have low molecular weights. As a result, the escape velocity required to escape Earth's gravitational field is lower than the average velocity of these gases at Earth's surface temperature. This means that hydrogen and helium would have escaped the Earth's atmosphere early on in its history when the gravitational field was weaker. Therefore, there is virtually no hydrogen and helium present in the atmosphere today.

Why Is There Virtually No Hydrogen and Helium Present in the Atmosphere