Question

In acidic solution, bromate ion can be used to react with a number of metal ions. One such reaction is

BrO3−(aq)+Sn2+(aq)→Br−(aq)+Sn4+(aq)

Since this reaction takes place in acidic solution, H2O(l) and H+(aq) will be involved in the reaction. Places for these species are indicated by the blanks in the following restatement of the equation:

BrO3−(aq)+Sn2+(aq)+     −−−→Br−(aq)+Sn4+(aq)+     −−−

What are the coefficients of the six species in the balanced equation above? Remember to include coefficients for H2O(l) and H+(aq) in the appropriate blanks.

Enter the equation coefficients in order separated by commas (e.g., 2,2,1,4,4,3).

Answer 1

oxidation :

Sn+2 (aq) -----------------------> Sn+4 (aq) + 2e-

reduction
BrO3- --------------------> Br-

+5                                    -1

BrO3- + 6e- -------------------> Br-

BrO3- + 6H+ + 6e- ------------------> Br- + 3H2O

overall balanced equation:

BrO₃⁻(aq)+ 3 Sn²⁺(aq)+ 6H⁺ (aq)    ----------------->   Br⁻(aq)+ 3 Sn⁴⁺(aq)+ 3H₂O(l)

coefficients = 1,3,6,1,3,3