Question

Смешали 200г 10% AgNO3 и 300г 20% HCl. Какова масса осадка?

Answer 1

Дано
m(ppaAgNO3)=200 g
W(AgNO3)=10%
m(HCL)=300 g
W(HCL)=20%
--------------------
m(AgCL)-?
m(AgNO3)=200*10%/100% = 20 g
M(AgNO3)=170 g/mol
n(AgNO3)=m/M=20/170=0.12 mol
m(HCL)=300*20%/100%=60 g
M(HCL)=36.5 g/mol
n(HCL)=m/M=60/36.5=1.64 mol
n(AgNO3)<n(HCL)
  20                        X
AgNO3+HCL-->AgCL+HNO3 M(AgCL)=143.5 g/mol
  170                    143.5
X=20*143.5 / 170
X=16.88 g
ответ 16.88 г