Answer:
= 32.39 %
Step-by-step explanation:
The relative atomic mass of sodium is 23, sulphur 32 while oxygen as a relative atomic mass of 16.
I mole of Na₂SO₄ has a relative mass of 2(23) + 32 + 4(16) = 142 grams
Of the value 142, the contribution of sodium is 2×23 =46
Thus the % composition is calculated:
46/142×100%= 32.39%