Дано
W(HCL)=10%
m(ppa NaOH)=10 g
w(NaOH)=5%
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m(ppa HCL)-?
находим массу веществаNaOH
m(NaOH)=10*5%/100%=0.5 g
0.5 g Xg
NaOH+HCL-->NaCL+H2O M(NaOH)=40 g/mol , M(HCL)=36.5 g/mol
40 36.5
X=0.5*36.5/40
X=0.45625 g
m(ppa HCL)=0.45625*100%/10%=4.5625 g
ответ 4.5625 г