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`13.4 g` of a sample of unstable hydrated salt `Na_(2)SO_(4).XH_(2)O` was found to contains `6.3 g` of `H_(2) O`. The number of molecular of water of crystalistion isA. 5B. 7C. 2D. 10 |
Answer» Correct Answer - B Weight of salt `= 13.4 g` weight of `H_(2) O = 6.3 g` Weight of anhydrous salt `= 13.4 - 6.3 = 7.1 g` Moles of anhydrous salt `= (7.1)/(842) = 0.05` Moles of `H_(2) O = (6.3)/(18) = 0.35 "mol"` `0.05 "mol"` of anhydrous salt `implies 0.35 "mol of" H_(2)O` 1 mole of anhydrous salt `implies (0.35)/(0.05) = 7 "mol"` |
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