md FeCl3 = 50*25/100=12.5 g FeCl3
3 KOH + FeCl3 ---> 3 KCl + Fe(OH)3
3*56 g KOH........162,5 g FeCl3.......107 g Fe(OH)3
x g KOH...............12,5 g FeCl3...........y g Fe(OH)3
x = 12.923 g KOH => ms = 12.92/10*100 = 129.2 g solutie KOH
y = 8,23 g Fe(OH)3