Đáp án:

37,74 gam. 

Giải thích các bước giải:

\(\rm C_2H_5OH(aq)+C_2H_5COOH(aq)\rightleftharpoons C_2H_5COOC_2H_5(aq)+H_2O(l)\)

\(\rm n_{C_2H_5OH\ bđ}=\dfrac{23}{46}=0,5(mol);n_{C_2H_5COOH\ bđ}=\dfrac{37}{74}=0,5(mol)\)

Đặt \(\rm n_{C_2H_5COOC_2H_5\ cb}=x(mol)\)

Theo PT: \(\rm n_{H_2O}=n_{C_2H_5OH\ pứ}=n_{C_2H_5COOH\ pứ}=x(mol)\)

\(\rm\to n_{C_2H_5OH\ cb}=n_{C_2H_5COOH\ cb}=0,5-x(mol)\)

\(\rm\to K_C=\dfrac{[C_2H_5COOC_2H_5].[H_2O]}{[C_2H_5OH].[C_2H_5COOH]}=\dfrac{x.x}{(0,5-x)(0,5-x)}=7,5\)

\(\rm\to x\approx 0,37\ (nhận)\) hoặc \(\rm x\approx 0,79\ (loại)\)

\(\rm\to m_{C_2H_5COOC_2H_5\ cb}=0,37.102=37,74(g)\)