berapa fraksi mol zat terlarut jika suatu larutan mengandung 15% berat asam sulfat (H2SO4)?

Misalkan massa larutan = 100 gram
Mr H2SO4 = 98
Mr H2O = 18
H2SO4 = 15/100 × 100 gr = 15 gr = 15/98 mol = 0,153 mol
H2O = 100 - 15 = 85 gr = 85/18 mol = 4,722 mol
Fraksi mol H2SO4
= mol H2SO4/(mol H2SO4 + mol H2O)
= 0,153/(0,153+4,722)
= 0,0314