Question

Complete and balance the equation where Cl2 reacts with Ag+ in an acidic solution to yield AgCl(s) and ClO3-.

Answer 1

Cl2 ---> Cl03-

first balance atoms other than O and H

Cl2 --> 2 Cl03-

now balance O atoms using H20

Cl2 + 6 H20 --> 2 Cl03-

now balance H atoms using H+

Cl2 + 6 H20 ---> 2 Cl03- + 12 H+

now balance charge using e-

Cl2 + 6 H20 ---> 2 Cl03- + 12 H+ + 10e-

now

consider the reaction

Cl2 + Ag+ ---> AgCl

first balance the atoms other than O and H

Cl2 + 2Ag+ ---> 2 AgCl

there are no O and H atoms

so balance charge using e-

Cl2 + 2 Ag+ + 2e- ---> 2 AgCl

now

write both the equations so that e- are equal

so

Cl2 + 6 H20 ---> 2 Cl03- + 12 H+ + 10e-

5Cl2 + 10 Ag+ + 10e- ---> 10 AgCl

cancel out the electrons

we get

6 Cl2 + 6H20 + 10Ag+ ---> 2 Cl03- + 12H+ + 10 AgCl

3 Cl2 + 3H20 + 5 Ag+ --> Cl03- + 6H+ + 5 AgCl