\(n_{CO_2}=\dfrac{V}{24,79}=0,2\left(mol\right)\)
PTHH: \(R_2CO_3+2HCl\rightarrow2RCl+CO_2+H_2O\)
Mol: 0,2 0,2
\(\Rightarrow n_{R_2CO_3}=0,2\left(mol\right)\)
Mặt khác: \(n_{R_2CO_3}=\dfrac{m}{M}\Rightarrow\dfrac{m}{M}=0,2\)
\(\Rightarrow M=\dfrac{m}{0,2}\Leftrightarrow2R+12+3\cdot16=\dfrac{21,2}{0,2}\)
\(\Rightarrow R=23=Na\)
\(\Rightarrow\left\{{}\begin{matrix}\%Na=\dfrac{2M_{Na}}{M}\cdot100\%=\dfrac{2\cdot23}{23\cdot2+12+16\cdot3}\cdot100\%\approx43,4\%\\\%O=\dfrac{3M_O}{M}\cdot100\%=\dfrac{3\cdot16}{23\cdot2+12+16\cdot3}\cdot100\%\approx45,3\%\\\%C=100\%-\%Na-\%O\approx11,3\%\end{matrix}\right.\)