Question

1)Calculeaza concentratia unei solutii care contine 18g sare dizolvata in 72 grame de apa.

2)Maria dizolva 30g sare in 50g apa.Ce concentratie va avea solutia obtinuta?

3)Victor dizolva 30g alcool in 170g de apa.Ce concentratie va avea solutia obtinuta?

4)Silvia dizolva 125g zahar in 375g apa.Ce concentratie va avea solutia obtinuta?

Dau coroana​

Answer 1

Răspuns:

1.

md=18g sare

ms=72 g apa

C=100×md/ms

C=18×100/72

C=1800/72

C=75%

2.

md=30g

mapa=50g

ms=50+30=80g

C=30×100/80=36,5%

3.

md=30g

mapa =179g

ms=30+170=200g

C=30×100/200=15%

4.

md=125g

mapa =375g

ms=125+375=500g

C=125×100/500=25%