дано
m (NaOH)=30г
m(H2SO4)=49г
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Мф(соли)=?
m(соли)=?
M(NaOH) = 40 g/mol
n(NaOH) = m/M = 30 / 40 = 0.75 mol
M(H2SO4) = 98 g/mol
n(H2SO4) = m/M = 49 / 98 = 0.5 mol
n(NaOH) > n(H2SO4)
2NaOH+H2SO4-->Na2SO4+2H2O
M(Na2SO4) = 142 g/mol
n(H2SO4) = n(Na2SO4) = 0.5 mol
m(Na2SO4) = n*M = 0.5 * 142 = 71 g
ответ 142 г/моль, 71 г