Question

Daca se dizolva 700 graMe de NaCl de concentratie de concentratie 60 la suta cu 500 ml.H2O ce concentratie2 are solutia finala.
va rog repede

Answer 1

ms = 700 g , c% = 60%

stim ca c% = mdx100/ms

m.apa = 500 g (ro.apa = 1 g/ml)

md = msxc%/100 = 700x60/100 = 420 g

ms.final = 700+500 = 1200 g

=> c%.inala = mdx100/ms.final

= 420x100/1200 = 35%