Reactions of Acids & Making Salts

Acids with metals

• Acid + metal $\rightarrow$ salt + hydrogen
• $\text{Mg} + \text{H}_2\text{SO}_4 \rightarrow \text{MgSO}_4 + \text{H}_2$; $\text{Zn} + 2\text{HCl} \rightarrow \text{ZnCl}_2 + \text{H}_2$
• You need the reactions of magnesium, zinc and iron with hydrochloric and sulfuric acids
• (HT) These are redox reactions: the metal atom loses electrons (oxidised) and the hydrogen ions gain electrons (reduced). $\text{Mg} + 2\text{H}^+ \rightarrow \text{Mg}^{2+} + \text{H}_2$