Balance the following redox equation: PbO2 + SO32- ==> Pb2+ + SO42-

To balance redox equations, do the following steps:
-Divide into 2 half equations
-Balance the formula EXCEPT for oxygen and hydrogen
-Balance the number of oxygens by adding water
-Balance the number of hydrogens adding hydrogen ions/protons
-Balance the charge by adding electrons
-Compare the half equations, and make sure the number of electrons in each is equal. If not, multiply each half equation to make sure they are
-Combine the half equations and cancel common things on both sides

With the example in the question:

PbO2 + SO32- ==> Pb2+ + SO42-

Split into half equations: PbO==> Pb2+                                      SO32- ==> SO42-
Balance formula (not needed here): PbO2 ==> Pb2+                   SO32- ==> SO42-
Balance oxygen:  PbO2 ==> Pb2+ + 2H2O                                 SO32- + H2O ==> SO42- 
Balance hydrogen: PbO2 + 4H+ ==> Pb2+ + 2H2O                    SO32- + H2O ==> SO42- + 2H+ 
Balance charge: PbO2 + 4H+ + 2e- ==> Pb2+ + 2H2O              SO32- + H2O ==> SO42- + 2H+ + 2e- 
Equal no. electrons (not needed here): PbO2 + 4H+ + 2e- ==> Pb2+ + 2H2O         SO32- + H2O ==> SO42- + 2H+ + 2e- 
Combine: PbO2 + 4H+ + 2e- + SO32- + H2O ==> Pb2+ + 2H2O + SO42- + 2H+ + 2e- 
Cancel and complete!: PbO2 + 2H+ + SO32- ==> Pb2+ + H2O + SO42- 

Answered by Zain C. Chemistry tutor

11998 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

What is the difference between structural isomers and stereoisomers?


Write a balanced equation for the reaction between NaOH and sulfuric acid. A conical flask contains 25cm^3 of 0.124M NaOH, a burette contains 0.0625M sulfuric acid. Find the minimum amount of acid required to completely react with the NaOH in the flask.


Why does ice float on water?


A naturally occurring sample of the element boron has a relative atomic mass of 10.8 In this sample, boron exists as two isotopes. Calculate the percentage abundance of 10B in this naturally occurring sample of boron.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences