\textbf{207-} If the chemical formula of a metallic phosphate is written as $\text{X}_m(\text{PO}_4)_n$, the chemical formula of its sulfide and nitride compounds, from right to left, and the possible group of this metal in the periodic table, should be:
\begin{center}
(1) $8,\ \text{X(NO}_3)_2,\ \text{XSO}_4$ \hspace{1cm} (2) $8,\ \text{X}_2\text{N}_2,\ \text{XS}$\\[4pt]
(3) $2,\ \text{XNO}_3,\ \text{X(SO}_4)_2$ \hspace{1cm} (4) $2,\ \text{X}_2\text{N}_2,\ \text{XS}$
\end{center}
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\textbf{Chemistry \hfill 122-D \hfill Page 19}
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