| 1. | When green coloured ferrous sulphate crystals are heated, the colour of the crystal changes because ? | |
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it forms SO3
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it forms SO2
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it loses water of crystallisation
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it is decomposed to ferric oxide
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Report Question| 2. | A substance which oxidises itself and reduces other is known as ? | |
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reducing agent
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oxidising agent
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both of these
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none of these
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| 3. | One of the following is an endothermic reaction. This is ? | |
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Combination of zinc and hydrochloric acid to form zinc chloride and hydrogen
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Combination of carbon and oxygen to form carbon monoxide
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Combination of nitrogen and oxygen to form nitrogen monoxide
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Combination of glucose and oxygen to form carbon dioxide and water
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| 4. | Why Magnesium ribbon is cleaned before burning ? | |
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It’s outer layer form oxides which interfere with burning.
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Dust from the atmosphere prevents its burning.
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It absorbs moisture from the atmosphere which interferes with burning.
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All of the above
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| 5. | When Ag is exposed to air it gets a black coating of ? | |
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Ag2S
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AgNO3
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Ag2CO3
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Ag2O
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| 6. | Which of the following is an endothermic process ? | |
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Respiration in human beings
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Condensation of water vapours
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Sublimation of dry ice
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Dilution of sulphuric acid
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| 7. | Which of the following involves combination of two elements ? | |
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NH3(g) + HCl(g) -> NH4Cl(s)
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2SO2(g) + O2(g) -> 2SO3f(g)
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CaO(s) + CO2(g) -> CaCO3(g)
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N2(g) + 3H2(g) -> 2NH3(g)
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| 8. | Which of the following are exothermic processes ? | |
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Evaporation of water, Sublimation of camphor (crystals)
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Reaction of water with quick time, Sublimation of camphor (crystals)
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Reaction of water with quick time, Dilution of an acid
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Dilution of an acid, Evaporation of water
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| 9. | What happens when dilute hydrochloric acid is added to iron filling Tick the correct answer ? | |
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Iron salt and water are produced
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Hydrogen gas and iron chloride are produced
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No reaction takes place
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Chlorine gas and iron hydroxide are produced
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| 10. | In a context of redox reactions, the removal of hydrogen from a substance is known as ? | |
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Dehydrogenation
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Reduction
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Oxidation
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hydration
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