ecuatile reactiilor: Ca + 1/2O2---> CaO
CaO+H2O-->Ca(OH)2
rezulta 1molCa....1 mol Cao...1molH2O.....1mol Ca(OH)2
40g.............56g.................18g.................(56+18_)g
20g...........m=28g...........m=9g...............m=37g
solutia obtinuta este alcatuita din
md=37gCa(OH)2
m,apa= 500-9---> 491g
ms= md+m,apa==> 491+37
c= mdx100/ms inlocuieste si calculeaza c !!!