Explain that volcanic activity released gases that formed the early atmosphere.

In the subtopic The Earth's early atmosphere, this learning objective focuses on explain that volcanic activity released gases that formed the early atmosphere. Within The composition and evolution of the Earth's atmosphere, students should explain this idea in the exact curriculum context rather than as an isolated fact. Approved keywords for this objective include early atmosphere and volcanic activity. early atmosphere means the Earth's atmosphere during its initial formation, likely composed mainly of carbon dioxide with little or no oxygen. Avoid students often think that volcanic activity only released carbon dioxide and did not consider other gases; instead remember that volcanic activity released a variety of gases, including water vapour and nitrogen, in addition to carbon dioxide. For exam answers, focus on how volcanic activity contributed to the formation of the Earth's early atmosphere by releasing gases.