Which of these is true of the oxygen in Earth's atmosphere?
A) Oxygen is the most abundant gas in Earth's atmosphere.
B) Oxygen is very chemically reactive.
C) The oxygen in Earth's atmosphere exists not as pure oxygen but only in chemical combination with hydrogen in water, carbon in carbon dioxide, and nitrogen in nitrogen oxides.
D) Oxygen is the heaviest molecule in Earth's atmosphere.

Question

Quizplus · Accepted Answer

Oxygen is very chemically reactive, which is why it plays a crucial role in various chemical processes and biological systems. It readily forms compounds with most elements.

Which of These Is True of the Oxygen in Earth's