Question

The atmosphere was filled with poisonous gases during the:

Hadean Eon
Archean Eon
Protozoic Eon
Phanerozoic Eon

Answer 1

The atmosphere was filled with poisonous gases during the Archean Eon.

The Archean Eon refers to the earlier of the two formal divisions of Precambrian time. During this time period, life was first formed on Earth. The Archean Eon began about 4 billion years ago with the formation of Earth’s crust and spanned to the start of the Proterozoic Eon 2.5 billion years ago. The Proterozoic Eon is the second formal division of Precambrian time.

Answer 2

The correct answer for the question that is being presented above is this one: "Archean Eon." The atmosphere was filled with poisonous gases during the Archean Eon. During the Archean Eon, it was likely a reducing atmosphere of methane, ammonia, and other gases which would be toxic to most life on our planet today.