MCaSO4=ACa+AS+4*AO=40+32+4*16=136
1mol CaSO4....136gCaSO4...40gCa
10moli CaSO4...xgCaSO4...400gCa
x=136*400/40=1360 g CaSO4
MH2SO4=2*AH+AS+4*AO=2*1+32+4*16=98
y g H2SO4/98=1360g/136 => y=98*1360/136=980g H2SO4 reacționat
c=md*100/ms => ms=md*100/c ms=980*100/20=4900 g soluție H2SO4