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What happens when calcium burns in oxygen?

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A labeled diagram of the periodic table entry for calcium, showing its atomic number 20, symbol Ca, atomic weight 40.078, electron configuration, and classification as an alkaline-earth metal. Icons indicate calcium is a solid with a face-centered cubic crystal structure and strongly basic oxides at room temperature. — calcium The chemical element calcium is the most abundant metallic element in the human body.

When calcium burns in air or pure oxygen, it reacts to form calcium oxide, which is also known as quicklime.1

Under normal conditions, the metal reacts more slowly with the oxygen, water vapor, and nitrogen present in the air, which results in the formation of a yellow coating consisting of a mixture of the oxide, hydroxide, and nitride.1