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प्रश्न
Which of the following substances are elements ?
Water, Salt, Mercury, Iron, Marble, Diamond, Wood, Nitrogen, Air, Graphite, Hydrogen, Oxygen, Sugar, Chlorine
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उत्तर
Mercury, iron, diamond, nitrogen, graphite, hydrogen, oxygen, and chlorine are elements because these cannot be split further into two or more simpler substances.
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संबंधित प्रश्न
Define the following term of Matter .
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A, B and C are all liquids. Liquid A has a comparatively low boiling point. On heating, liquid A vaporises completely without leaving behind any residue. Liquid A is being used increasingly as a fuel in motor vehicles either alone or by mixing with petrol. Liquid B has a very high boiling point. It also vaporises completely on heating, without leaving any residue. Liquid B is a conductor of electricity and used in making thermometers. Liquid C has a moderate boiling point. On heating, liquid C vaporises leaving behind a white solid D which is used in cooking vegetables. The condensation of vapours from C give a liquid E which turns anhydrous CuSO4 to blue.
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(b) Which liquid could be a mixture ? Name this mixture.
(c) Which liquid could be a compound ? Name this compound.
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(e) What do you think is liquid E ?
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What is a colloid ? Give two examples of colloids (or colloidal solutions)
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(c) Name a metal which you think could behave like solid A. Also name the products B and C.
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- What could Y be ?
- Name the process Z.
- Which process would you use to recover both the components X and Y from tincture of iodine ?
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