Question

Sebanyak 200 gram Na2SO4 dengan kadar 71% mengandung Na, S, dan O, sebanyak... gram
(Ar Na =23, S = 32, O = 16)

Answer 1

M Na₂SO₄ = 200 gr
Mr Na₂SO₄ = 142
kadar = 71%

m Na₂SO₄ murni =   × 200 gr = 142 gr

m Na =   × koef. Na × m Na₂SO₄
          =  × 2 × 142 gr
          = 46 gr

m S =   × koef. S × m Na₂SO₄
        =  × 1 ×142
        = 32 gr

m O =   × koef. O × m Na₂SO₄
        =  × 4 × 142
        = 64 gr