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How many moles of Na are present in 120 g Sodium sulphate. |
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Answer» Molar mass of Sodium sulphate (Na2SO4)- = 2(23)+32+4(16) = 46+32+64 = 142 g/mol Number of moles of Na2SO4 in 120 grams of it: No. of moles = Molecular mass/ Molar mass No. of moles = 120/142 = 0.845 moles Now, in each mole of sodium sulphate, there are 2 moles of Sodium (Na). Therefore, 0.845×2 = 1.69 moles of sodium are present in 120 grams of sodium sulphate. Na2SO4(sodium sulphate) Molecular weight - 142 g/mol Number of moles of sodium sulphate = \(\frac{120g}{142g/mol} = 0.84 mole\) \(\because\) 1 molecule of Na2SO4 contains = 2 atom of sodium \(\therefore\) 0.84 mole of Na2SO4 contain = 1.68 moles sodium atom. Hence, 120 g Na2SO4 contain 1.68 moles sodium atom |
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