Дано
V(HCL)=1 L
w(HCL)=30%
p(HCL)=1150 g/L
V(H2O)=5 L=5000 мл
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W1(HCL)-?
m(HCL)=V(HCL)*p(HCL)*W(HCL) / 100%
m(HCL)=1*1150*30/100=345 g
m(H2O)=p(H2O)*V(H2O) = 1*5000 = 5000 g , p(H2O)=1 g/mL
m(ppa)=m(HCL)*m(H2O)=345+5000=5345 g
W1(HCL)=m(HCL) / m(ppa) * 100%= 345/5345*100=6.45%
ответ 6.45%