In acidic solution, the bromate ion can be used to react with a number of metal ions. One such reaction is
\rm \rm {BrO_3}^-{(aq)}+Sn^{2+}{(aq)}\rightarrow \rm Br^-{(aq)}+Sn^{4+}{(aq)}
Since this reaction takes place in acidic solution, \rm H_2O{(l)} and \rm H^+{(aq)} will be involved in the reaction. Places for these species are indicated by the blanks in the following restatement of the equation