Răspuns:
a)Se dă: m(NaCl)=m(sol)*ω/100%
m(sol)=120g m(NaCl)=120g*5%/100%=6g
ω=5% m(H₂O)=120g-6g=114g
m(NaCl)-?
m(H₂O)-?
b)Se dă: m(NaCl)=8%*200g/100%=16g
m(sol)=200g m(H₂O)=200g-16g=184g
ω=8%
m(NaCl)-?
m(H₂O)-?
c)m(sol)=250g m(NaCl)=1%*250g/100g=2,5g
ω=1% m(H₂O)=250g-2,5g=247,5g
m(NaCl)-?
m(H₂O)-?
Explicație:sper ca team ajutat