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Question
Potassium nitrate on strong heating decomposes as under :
2KNO3 → 2KNO2 + O2
Calculate : Weight of potassium nitrite formed.
(K = 39, 0 = 16, N = 14)
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Solution
From the equation :
Molecular weight of KNO3 = (Atomic mass of K + Atomic mass of N + Atomic mass of O) = (39 + 14 + 16 x 3 ) = 101
Molecular mass of of KNO2 = (39 + 14 + 16 x 2) = 85
From the reaction :
2 moles of KNO3 gives = 2 moles of KNO2
So, 202g of KNO3 gives = 170g of KNO2
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