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प्रश्न
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 ______.
पर्याय
potassium dichromate solution and sulphur dioxide
potassium permanganate solution and sulphur dioxide
potassium permanganate solution and lemon juice
potassium dichromate solution and carbon dioxide
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उत्तर
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 potassium dichromate solution and sulphur dioxide.
Explanation:
Potassium dichromate (K2Cr2O7) is an oxidising agent that naturally forms a bright orange solution due to its dichromate ions. When sulphur dioxide (SO2) gas is passed through it, a redox reaction occurs where the sulphur dioxide acts as a reducing agent. This reduces the chromium ions from an oxidation state of +6 (orange) to +3 (green), turning the entire solution green.
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संबंधित प्रश्न
Write a complete balanced equation for the following reaction:
\[\ce{Sulphur dioxide (gas) + Oxygen (gas) -> Sulphur trioxide (gas)}\]
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\[\ce{H2O2 -> H2O + O2}\]
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\[\ce{Fe + O2 -> Fe2O3}\]
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Word equation:
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