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प्रश्न
Balance the following equation:
Na + O2
Na2O
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उत्तर
4Na + O2 → 2Na2O
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संबंधित प्रश्न
What is a chemical equation? Explain with the help of an example.
State one characteristic of the chemical reaction which takes place when quicklime is treated with water
Is Electrolysis of water an endothermic reaction or an exothermic reaction?
The chemical reaction between two substances is characterised by a change in colour from orange to green. These two substances are most likely to be:
(a) potassium dichromate solution and sulphur dioxide
(b) potassium permanganate solution and sulphur dioxide
(c) potassium permanganate solution and lemon juice
(d) potassium dichromate solution and carbon dioxide.
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(a) evolution of hydrogen gas
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(c) change in temperature of mixture
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sulphur + nitric acid→ sulphuric acid + nitrogen dioxide + water.
\[\ce{MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2}\]
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Match column A with column B.
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| (d) White to yellow when hot and white when cold. | (iv) Copper sulphate |
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\[\ce{N2 + 3H2 ⇌[Fe - 450°C][200 atoms] 2NH3 + \triangle}\]
Word equation:
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State what 200 atmospheres – indicates.
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CaC2 + N2 → 2CaCN2 + C
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What are products? Explain with the help of example.
Which among the following statement(s) is(are) true? ‘Exposure of silver chloride to sunlight for a long duration turns grey due to
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- sublimation of silver chloride.
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- oxidation of silver chloride.
