What were the dominant gases in Earth's second atmosphere?
A) nitrogen and oxygen
B) carbon dioxide and water vapor
C) methane and ammonia
D) hydrogen and helium

Question

Quizplus · Accepted Answer

The second atmosphere of Earth was dominated by carbon dioxide and water vapor, which were released from volcanic eruptions and contributed to a very different composition compared to the present atmosphere.

What Were the Dominant Gases in Earth's Second Atmosphere