Câu 8:
\(n_{C_2H_5OH}=\dfrac{4,6}{46}=0,1\left(mol\right)\)
PT: \(C_2H_5OH+O_2\underrightarrow{^{mengiam}}CH_3COOH+H_2O\)
Theo PT: \(n_{CH_3COOH\left(LT\right)}=n_{C_2H_5OH}=0,1\left(mol\right)\)
\(\Rightarrow m_{CH_3COOH\left(LT\right)}=0,1.60=6\left(g\right)\)
\(\Rightarrow H=\dfrac{4,8}{6}.100\%=80\%\)
Đáp án: A