Question

48 g solutie de concentratie 30% se fierb obtinandu-se o noua solutie de concentratie 50% . Calculati masa de apa care s a evaporat.

Answer 1

ms1=48 g
c1=30%
md=ms1*c1/100= 48*30/100=14,4 g
ms2= ms1-m
c2=50%
md=ms2*c2/100
(ms1-m)*c2=100*md
(48-m)*50=100*14,4
48-m=28,8
m=19,2 g apa s-au adaugat