MCQ
Which one of the following is not an element
- ADiamond
- BGraphite
- ✓Silica
- DOzone
✓
Answer
Correct option: C.
Silica
c
Silicon dioxide is known as silica with molecular formula $= SiO _2$ which is a compound, not an element.
Silicon dioxide is known as silica with molecular formula $= SiO _2$ which is a compound, not an element.
Diamond and graphite are purely made up of carbon i.e $C$, an element.
Ozone is trioxygen molecule i.e $O _3$, an element.
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