Răspunsuri

2014-03-10T21:33:11+02:00
C%=(md/ms)*100=>ms=(md/c)*100=(500/25)*100=2000 g 
ms = md + mH2O=>m apa = ms - md=2000-500=1500g H2O
la 1500 g H2O.........500 g cristalorhidrat
la x g H2O.........250 g cristalorhidrat (masa molara a cristalorhidratului)
x=750 g H2O
densitatea=masa/volum=>V apa = 750/1=750 cm^3=0,75 l H2O