Question

what mass of NaOH would be needed to neutralize exactly 200cm of a solution containing 4.9g per dm of H2SO4

Answer 1

2NaOH + H2SO4 ==> Na2SO4 + 2H2O

4.9 g H2SO4 is how many moles? That's mols = g/molar mass = 4.9/98 = 0.05. The equation tells you that you will need twice that or 0.05 x 2 = 0.1 mol NaOH. How many grams is that? g NaOH = mols NaOH x molar mass NaOH = ?
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