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प्रश्न
Which of the following is not an element ?
पर्याय
graphite
germanium
silica
silicon
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उत्तर
Silica.
Silica is a compound made up of Si (silicon) and O (oxygen) and chemically called Silicon dioxide.
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संबंधित प्रश्न
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| Column A | Column B | ||
| (a) | Molecules | (i) | Water boils |
| (b) | 100° C | (ii) | Evaporation |
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| (d) | At all temperatures | (iv) | Matter |
| (e) | Camphor | (v) | Water freezes |
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