MCQ
What is the most abundant element on earth?
- A
- B
- ✓
- D
✓
Answer
Correct option: C.
(c): Oxygen occurs in the free state as dioxygen $\left( O _2\right)$ and makes up $20.46 \%$ by volume and $23 \%$ by mass of the atmosphere and $46.6 \%$ by weight of the earth's crust where it mainly occurs as silicate minerals.
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