Дано
m(ppa NAOH)=50 g
W(NaOH)=40%
m(HNO3)=50 g
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m(NaNO3)-?
m(NaOH) = 50*40%*100%=20 g
M(NaOH)=40 g/mol
n(NaOH)=m/M=20/40 = 0.5 mol
M(HNO3)=63 g/mol
n(HNO3)=m/M=50 / 63=0.8 mol
n(NaOH) 20 X
NaOH+HNO3-->NaNO3+H2O M(NaNO3)=85 g/mol
40 85
X=20*85 / 40
X=42.5 g
ответ 42.5 г