Question

Am 200 g saramura de concentratie 10%. Sa se determine concentratia molara stiind ca ea are densitatea de 1,2 g/mol.

Answer 1

Saramura = solutie NaCl
Volumul solutiei:

V=m/p=200/1,2=166,66cm^3=0,16666L

Masa de NaCl=10/100*200=20g
M NaCl=A Na + ACl=58,5g/mol
n NaCl=20/58,5=0,34188moli

cM=n/V=0,34188/0,16666=2,0512M (aprox. 2M)