👤

1) Ce cantitate de apa se gaseste in 40 kg de concentratie 13%

Răspuns :

C=13% ms=md×100÷C=40kg×100÷13=4000÷13=307,(692307)
md=40kg mapa=ms-md=307,(692307)-40=277,(692307)
mapa=?
ms=40kg
c= mdx100/ms
13/100= md/40-----> md= 5,2kg substanta dizolvata in cele 40kg solutie
ms= md+m,apa;  m,apa = 40-,5,2=.................calculeaza kg apa