How many grams of sodium sulphate (mol. wt. 142) are required to make 1.2 liters of 0.5N solution

Answer 1

Technically one can't calculate this without knowing the reaction involved; however, is most problems of this type the usual is to use total + and - charge.
Therefore, equivalent weight Na2SO4 = molar mass/+ charge = 142/2 = 81.
How many equivalents do you need? That's
N x L = 0.5N x 1.2L = ?
Then ?equivalent x equivalent weight = grams Na2SO4.

Answer 2

48.6