Bài 1:
\(a,d_{O_2/CO_2}=\dfrac{32}{44}\approx0,73\\ b,d_{O_2/Cl_2}=\dfrac{32}{71}\approx0,45\\ c,d_{O_2/SO_2}=\dfrac{32}{64}=0,5\\ d,d_{O_2/N_2}=\dfrac{32}{28}\approx1,14\)
Bài 2:
\(a,\left\{{}\begin{matrix}\%_{Na}=\dfrac{46}{142}\cdot100\%\approx32,39\%\\\%_S=\dfrac{32}{142}\cdot100\%\approx22,54\%\\\%_O=100\%-32,39\%-22,54\%=45,07\%\end{matrix}\right.\)
\(b,\left\{{}\begin{matrix}\%_{Mg}=\dfrac{24}{84}\cdot100\%\approx28,57\%\\\%_C=\dfrac{12}{84}\cdot100\%\approx14,29\%\\\%_O=100\%-28,57\%-14,29\%=57,14\%\end{matrix}\right.\)
\(c,\left\{{}\begin{matrix}\%_{Fe}=\dfrac{56\cdot2}{56\cdot2+16\cdot3}\cdot100\%=\dfrac{112}{160}\cdot100\%=70\%\\\%_O=100\%-70\%=30\%\end{matrix}\right.\)
\(d,\left\{{}\begin{matrix}\%_S=\dfrac{32}{32+16\cdot2}\cdot100\%=\dfrac{32}{64}\cdot100\%=50\%\\\%_O=100\%-50\%=50\%\end{matrix}\right.\)