Question

Se dizolva o masa de sare in 423g apa obtinandu-se o solutie de concentratie 40%.Calculeaza masa de sare necesara obtinerii acestei solutii. Va rog mult!​

Answer 1

C%=md/(md+ms)x100
40=md/(md+423)x100
md/(md+423)=0,4
md=0,4md+169,2
md-0,4md=169,2
0,6md=169,2
md=282g

Answer 2

Răspuns:

c=md/md+mapa×100=)40=md/md+423×100=)40/100=md/md+mapă

40 (md+423)=10×md=)40×md+40×423=10×md=)40×md+16920=10×md=)30×md=16920=)md=16920:30=564g