Răspuns:
Explicație:
c=49%
400g sol.Ca(OH)2
c=14,8%
ms H3PO4
-se afla md sol. de Ca(OH)2
md=c . ms :
md=14,8 . 400 : 100=59,2 g Ca(OH)2
xg 59,2g
2 H3PO4 + 3Ca(OH)2 = Ca3(PO4)2+6 H2O
2 .98g 3. 74g
x=2 .98 . 59,2 : 3 .74= 52,26 gH3PO4
-se afla ms H3PO4
ms= md.100: c
ms= 52,26 .100 : 4,9=1066,5 g H3PO4
MH3PO4=3+31+4.16=98------->98g/moli
MCa(OH)2 =40+2+2.16=74------> 74g/moli
