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Question
A chemical reaction is often accompanied by external indications or characteristics.
Solution
A chemical reaction is accompanied by a change in colour of reactants and products
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A .............is a substance which changes the rate of a chemical reaction without undergoing a chemical change.
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- temperature and Pressure
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- presence of catalyst
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Solution
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Hydrogen sulphide |
Ammonia |
Sulphur dioxide |
Hydrogen chloride |
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Shake the gas with red litmus solution |
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Shake the gas with blue litmus solution |
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