Question

volumul de solutie apoasa de HCl de concentratie procentuala masica 36,5% (densitatea=1,25g/mL) necesar pt a prepara 400 ml solutie de Cncentratie 2,5M.

Answer 1

CM=n/v => n=CM•v= 2,5M•0,4L=1 mol HCl
n=m/M => m=n•M=1 mol • 36,5g/mol
=> m=36,5g (md)
c=md•100/ms => ms= md•100/c <=> ms=36,5g•100/36,5=100g
ro•v=m => v=m/ro= 100g/(1,25g/mL) = 80mL soluție HCl => V HCl = 0,08 L