213. At room temperature, 250 mL of barium hydroxide solution contains 427.5 milligrams of it. The pH of this solution is: and 150 mL of it reacts completely with phosphoric acid; how many milligrams of insoluble product form in water? $(H = 1,\ O = 16,\ P = 31,\ Ba = 137\ \text{g.mol}^{-1})$ (The balanced reaction equation is:) $\mathrm{Ba(OH)_2(aq) + H_3PO_4(aq) \rightarrow Ba_3(PO_4)_2(s) + H_2O(l)}$ (1) $355/5$ , $12$ (2) $355/5$ , $12/3$ (3) $255/5$ , $12$ (4) $255/5$ , $12/3$
\textbf{213.} At room temperature, 250 mL of barium hydroxide solution contains 427.5 milligrams of it. The pH of this solution is: and 150 mL of it reacts completely with phosphoric acid; how many milligrams of insoluble product form in water?
$(H = 1,\ O = 16,\ P = 31,\ Ba = 137\ \text{g.mol}^{-1})$
(The balanced reaction equation is:) $\mathrm{Ba(OH)_2(aq) + H_3PO_4(aq) \rightarrow Ba_3(PO_4)_2(s) + H_2O(l)}$
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(1) $355/5$ , $12$ \hspace{2cm} (2) $355/5$ , $12/3$ \\
(3) $255/5$ , $12$ \hspace{2cm} (4) $255/5$ , $12/3$
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