Дано
W(HCL)=10%
m(ppa BA(OH)2=174 g
W(BaOH)=5%
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m(ppa HCL)-?
m(Ba(OH)2)=174*5% / 100%= 8.7 g
Xg 8.7 g
2HCL+Ba(OH)2-->BaCL2+2H2O
2*36.5 171
M(HCL)=36.5 g/mol , M(Ba(OH)2)=171 g/mol
X=73*8.7 / 171= 3.7 g
m(ppaHCL)=3.7*100% / 10% = 37 g
ответ 37 г