Sơ đồ phản ứng:
\(X+O_2\rightarrow CO_2+H_2O\)
Dẫn sản phẩm cháy vào nước vôi trong dư.
\(CO_2+Ca\left(OH\right)_2\rightarrow CaCO_3+H_2O\)
\(\Rightarrow n_{CaCO3}=n_{CO2}=\frac{45}{100}=0,45\left(mol\right)\)
\(m_{dd_{giam}}=m_{CaCO3}-\left(m_{CO2}+m_{H2O}\right)=14,4\)
\(\Rightarrow m_{CO2}+m_{H2O}=45-14,4=30,6\left(g\right)\)
\(m_{H2O}=30,6-0,45.44=10,8\left(g\right)\)
\(\Rightarrow n_{H2O}=\frac{10,8}{18}=0,6\left(mol\right)\)
BTNT:
\(n_C=n_{CO2}=0,45\left(mol\right)\Rightarrow m_C=0,45.12=5,4\left(g\right)\)
\(\Rightarrow\%m_C=\frac{5,4}{9}=60\%\)
\(n_H=2n_{H2O}=0,6.2=1,2\left(mol\right)\)
\(\Rightarrow\%m_H=\frac{1,2}{9}.100\%=13,33\%\Rightarrow\%m_O=26,67\%\)
