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प्रश्न
Explain why, graphite can be used as a lubricant but diamond cannot.
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उत्तर
Because of its softness and non-volatile nature, graphite is used as a lubricant in the fast moving parts of a machinery. It is used for lubricating the parts of machinery which operate at high temperatures. Diamond, on the other hand, is an extremely hard substance; therefore, it cannot be used as a lubricant.
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संबंधित प्रश्न
State the reason to explain why covalent compounds "have low melting and boiling points."
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Fill in the blank in the following sentence:
In forming N2 molecule, .............. electrons are shared by each atom of nitrogen.
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An element E exists in three allotropic forms A, B and C. In allotrope A, the atoms of element E are joined to form spherical molecules. In allotrope B, each atom of element E is surrounded by three other E atoms to form a sheet like structure. In allotrope C, each atom of element E is surrounded by four other E atoms to form a rigid structure.
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(b) What is allotrope A.
(c) What is allotrope B?
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(e) Which allotrope is used in making jewellery?
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