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Which of the following statements are incorrect? (A) 0.2 M, 500 mL of KMnO4 in alkaline medium can oxidise 0.08 mol of I⁻. (B) Acidified KMnO4 is used to estimate reducing agents in urine. (C) Combustion of CH4(g) is an example of an endothermic reaction. (D) In a*Cu + b*HNO3 -> Cu(NO3)2 + NO + H2O (dilute HNO3), b/a = 8/3.
- 0.2M 500 ml KMnO4 in alkaline medium oxidises 0.08 mol of I⁻
- Acidified KMnO4 is used to estimate reducing agents in urine
- Combustion of CH4(g) is an example of an endothermic reaction
- In a*Cu + b*HNO3 -> Cu(NO3)2 + NO + H2O, b/a = 8/3
Correct answer: Combustion of CH4(g) is an example of an endothermic reaction
Solution
Statement A is incorrect: equivalents of KMnO4 (0.1) do not match equivalents of I⁻ oxidised (0.48). Statement C is incorrect: CH4 combustion is exothermic, not endothermic. Statements B and D are correct.
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