If carbon was the most common element found in the moons and planets, what element is missing that would make them similar to earth? explain why. (hint: think about the carbon cycle.)

The element that is missing that would have made them similar to the earth is oxygen.

Carbon is one the most abundant elements on earth. It is a component of the all living things and the carbon cycle has an atmospheric, lithospheric and hydrospheric component.However, carbon is abundant in the moon and planets but the element that is missing that would have made them similar to the earth is oxygen. If oxygen were present in the moon and planets, then life forms world exists there and carbon may exist as carbon dioxide in the moon and the planets.

Hence, the most common element that would make the moon and planets similar to earth is oxygen.

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