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प्रश्न
Potassium chlorate decomposes, on heating, to form potassium chloride and oxygen. When 24.5 g of potassium chlorate is decomposed completely, then 14.9 g of potassium chloride is formed. Calculate the mass of oxygen formed. Which law of chemical combination have you used in solving this problem ?
उत्तर
Chemical reaction:
2KCIO3 → 2KCI + 3O2
24.5 g 14.9 g
So, mass of oxygen formed during the reaction:
Mass of reactants = 24.5 g
Mass of products = mass of the potassium chloride + mass of oxygen
24.5 = 14.9 + mass of oxygen
Mass of oxygen = 24.5 – 14.9 = 9.6 g
We have used the law of conservation of mass, proposed by Antoine Lavoisier, to solve this problem.
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