дано
m(ppa KOH) = 100 g
W(KOH) = 56%
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m(C2H5OH)-?
m(KOH) =100 * 56% / 100% = 56 g
HCOOC2H5+KOH-->HCOOK+C2H5OH
M(KOH) = 56 g/mol
n(KOH) = m/M = 56 / 56 = 1 mol
n(KOH) = n(C2H5OH) = 1 mol
M(C2H5OH) = 46 g/mol
m(C2H5OH) = n*M= 1 * 46 = 46 g
ответ 46 г