Question

Prin racirea a 1000 g solutie Ba(NO3)2, de concentratie 25,50% de la 100 grade C la 40 grade C se cristalizeaza 150 g Ba(NO3)2. Concentratia solutiei la 40 grade C este:
a)18,50%
b)12,35%
c)10,80%
d)15,00%

Answer 1

md=1000*25,5/100=255

mH2O=1000-255=745

255-150= 105

ms=745+105=850

c=105*100/850=12,35 %