The very first Earth atmosphere,forming with the Earth itself,was probably dominated by the cosmically abundant gases ________ and ________.

Question

Quizplus · Accepted Answer

The first Earth atmosphere was likely dominated by hydrogen and helium, which were abundant in the early universe and in the primordial gas cloud from which the solar system formed. Nitrogen and oxygen were not present in significant amounts until later in Earth's history, while carbon dioxide and methane were present in some capacity but would not have dominated the atmosphere. Water vapor and sulfur dioxide may have been present but would not have been the dominant gases.

The Very First Earth Atmosphere,forming with the Earth Itself,was Probably