4.2 Exercise 8

Classify the following as acid-base reactions or oxidation-reduction reactions:

(a) $\text{Na}_{2} \text{S} \left(a q\right) + 2 \text{HCl} \left(a q\right) \rightarrow 2 \text{NaCl} \left(a q\right) + \text{H}_{2} \text{S} \left(g\right)$

(b) $2 \text{Na} \left(s\right) + 2 \text{HCl} \left(a q\right) \rightarrow 2 \text{NaCl} \left(a q\right) + \text{H}_{2} \left(g\right)$

(c) $\text{Mg} \left(s\right) + \text{Cl}_{2} \left(g\right) \rightarrow \text{MgCl}_{2} \left(s\right)$

(d) $\text{MgO} \left(s\right) + 2 \text{HCl} \left(a q\right) \rightarrow \text{MgCl}_{2} \left(a q\right) + \text{H}_{2} \text{O} \left(l\right)$

(e) $\text{K}_{3} \text{P} \left(s\right) + 2 \text{O}_{2} \left(g\right) \rightarrow \text{K}_{3} \text{PO}_{4} \left(s\right)$

(f) $3 \text{KOH} \left(a q\right) + \text{H}_{3} \text{PO}_{4} \left(a q\right) \rightarrow \text{K}_{3} \text{PO}_{4} \left(a q\right) + 3 \text{H}_{2} \text{O} \left(l\right)$