230 – The difference between the sum of stoichiometric coefficients of substances a and d in the balanced equations of the reactions below, and then which reaction is of the oxidation–reduction (redox) type? \begin{align*} &\text{a) } \mathrm{Ca_3(PO_4)_2(s) + SiO_2(s) + C(s)} \xrightarrow{\Delta} \mathrm{P_4(g) + CaSiO_3(s) + CO(g)} &\text{b) } \mathrm{Ca_3(PO_4)_2(s) + H_2SO_4(aq) \to CaSO_4(s) + H_3PO_4(aq)} &\text{c) } \mathrm{HNO_3(aq) + I_2(g) \to I_2(s) + NO(g) + H_2O(l)} &\text{d) } \mathrm{PCl_5(g) + H_2O(l) \to H_3PO_4(aq) + HCl(aq)} \end{align*} (1) $2$ , $14$ (2) $2$ , $24$ (3) $3$ , $14$ (4) $3$ , $24$
\textbf{230 –} The difference between the sum of stoichiometric coefficients of substances \textbf{a} and \textbf{d} in the balanced equations of the reactions below, and then which reaction is of the oxidation–reduction (redox) type?
\begin{align*}
&\text{a) } \mathrm{Ca_3(PO_4)_2(s) + SiO_2(s) + C(s)} \xrightarrow{\Delta} \mathrm{P_4(g) + CaSiO_3(s) + CO(g)}\\
&\text{b) } \mathrm{Ca_3(PO_4)_2(s) + H_2SO_4(aq) \to CaSO_4(s) + H_3PO_4(aq)}\\
&\text{c) } \mathrm{HNO_3(aq) + I_2(g) \to I_2(s) + NO(g) + H_2O(l)}\\
&\text{d) } \mathrm{PCl_5(g) + H_2O(l) \to H_3PO_4(aq) + HCl(aq)}
\end{align*}
\begin{center}
(1) $2$ , $14$ \hspace{1.5cm} (2) $2$ , $24$ \hspace{1.5cm} (3) $3$ , $14$ \hspace{1.5cm} (4) $3$ , $24$
\end{center}
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