Em tham khảo nha:
\(\begin{array}{l}
CTHH\,\,:\,{S_x}{O_y}\\
{m_S} = 80 \times 40\% = 32g\\
{m_O} = 80 - 32 = 48g\\
{n_S} = \dfrac{m}{M} = \dfrac{{32}}{{32}} = 1\,mol\\
{n_O} = \dfrac{m}{M} = \dfrac{{48}}{{16}} = 3\,mol\\
x:y = {n_S}:{n_O} = 1:3\\
\Rightarrow CTHH:S{O_3}
\end{array}\)