\(\%_{Na_{\left(Na_2CO_3\right)}}=\dfrac{23.2}{23.2+12+16.3}.100\%\approx43,4\%\)
\(\%_{C_{\left(Na_2CO_3\right)}}=\dfrac{12}{23.2+12+16.3}.100\%\approx11,3\%\)
\(\%_{O_{\left(Na_2CO_3\right)}}=100\%-43,4\%-11,3\%=45,3\%\)
(Các chất còn lại tương tự.)