The reactions between acids and metals

The hydrogen ion in the voltage series of the metals

In water hydrogen ions are set free by acids. $H^+$ is an oxidising agent in the voltage series which can react only with metals which are stronger reductants than $H_2$ (non noble metals).

$Au^{3+}+3e^-$$Au$ $Hg^{2+}+2e^-$$Hg$ $Ag^{+}+e^-$$Ag$ $Cu^{2+}+2e^-$$Cu$ $2H^{+}+2e^-$$H_2$ $Pb^{2+}+2e^-$$Pb$ $Sn^{2+}+2e^-$$Sn$ $Fe^{2+}+2e^-$$Fe$ $Zn^{2+}+2e^-$$Zn$ $Al^{3+}+3e^-$$Al$ $Mg^{2+}+2e^-$$Mg$ $Na^{+}+e^-$$Na$ $Ca^{2+}+2e^-$$Ca$ $K^{+}+e^-$$K$ $Li^{+}+e^-$$Li$

Marked in red: noble metals which do not react with $H^+$ Marked in blue: non noble metals which react with $H^+$

Example: Chlorhydric acid and zinc

Zinc reacts with chlorhydric acid producing zinc chloride and hydrogen gas $2H^{+}+2e^-\longrightarrow H_2(g$) $Zn-2e^-\longrightarrow Zn^{2+}$ $Zn +2H^+\longrightarrow Zn^{2+}+H_2(g)$

The presence of metals in nature

Rain water contains $H^+$ ions coming from several acids, especially $H_2CO_3$: So non noble metals will be attacked by rain water in nature and cannot be found there in elementary form. On the other side $H^+$ cannot oxidise noble metals: $Au, Hg, Ag, Cu$. These metals can be found in their native states: Native (metallic) gold Native (metallic) silver Native (metallic) copper