Acid-metal reactions

Some metals react with acids to produce a salt and hydrogen gas. In each reaction, the metal replaces hydrogen from the acid and becomes part of the salt. The general word equation is:

\text{metal} + \text{acid} \rightarrow \text{salt} + \text{hydrogen}

The metal gives the salt the first part of its name. The acid determines the second part: hydrochloric acid forms a chloride, while sulfuric acid forms a sulfate. For example, magnesium forms magnesium chloride with hydrochloric acid and magnesium sulfate with sulfuric acid.

Acid-metal word and symbol equations

A word equation names the reactants and products. A symbol equation uses their chemical formulae and is balanced so that there are equal numbers of each type of atom on both sides.

Magnesium and hydrochloric acid produce magnesium chloride and hydrogen:

$\text{magnesium} + \text{hydrochloric acid} \rightarrow \text{magnesium chloride} + \text{hydrogen}$

\ce{Mg + 2HCl -> MgCl2 + H2}

Zinc and dilute sulfuric acid produce zinc sulfate and hydrogen:

$\text{zinc} + \text{sulfuric acid} \rightarrow \text{zinc sulfate} + \text{hydrogen}$

\ce{Zn + H2SO4 -> ZnSO4 + H2}

Iron and hydrochloric acid produce iron(II) chloride and hydrogen:

$\text{iron} + \text{hydrochloric acid} \rightarrow \text{iron(II) chloride} + \text{hydrogen}$

\ce{Fe + 2HCl -> FeCl2 + H2}