Ca (OH)2=40+2•16+2•1=40+32+2=74
Ca:O:H=40:32:2=20:16:1 (se simplifica, aici)
74gCa(OH)2......40gCa...16gO...1gH
100gCa(OH)2......x...........y............z
74\ (supra)100=40\x=x rezulta 100•40\74=54,05℅gCa
74\(supra)100=16\y=rezulta 100•16\74=21,62℅gO
74\(supra)100=2\z=rezulta 100•2\74=2,70℅gH
Pe cealalta o completezi tu...