Earth’s atmosphere is a mixture of oxygen, water vapor, and other gases. helium nitrogen hydrogen carbon

The right answer is nitrogen.

The chemical composition of the atmosphere essentially comprises nitrogen (78%), oxygen (21%), rare gases (Argon, Neon, Helium ...) and in the lower layers, water vapor and carbon dioxide.

The constituents of atmospheric air can be classified into two categories:

* constituents such as nitrogen, rare gases, whose concentration is constant, at least in the lower layers of the atmosphere.

* Constituents whose content varies in the atmosphere, such as carbon dioxide and especially water vapor.

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