Redox Titrations

Question 1

What is a redox titration?

Answer 1

Allows you to find out how much oxidising agent is needed to exactly react with a quantity of reducing agent

Question 2

Devise a redox titration using manganate(vii) ions(5)

Answer 2

– Measure out quantity of reducing agent e.g. Aqueous Fe2+ ions in a conical flask

– Add dilute sulphuric acid

– Add aqueous MnO4^-(oxidising agent) to the reducing agent using a burette

– Do a rough titration

– Do at least three accurate titrations which Are concordant

Question 3

Should the oxidising agent being the bureau it and the reducing agent in the conical flask or the other way round?

Answer 3

It doesn’t matter

Question 4

Why do you have to add die loot sulphuric acid in access to the flask?

Answer 4

To make sure there are plenty of H+ ions to allow the oxidising agent to be reduced

Question 5

What do you expect to happen when the titration reaction is complete?

Answer 5

Sharp colour change to pink in the flask

Question 6

What colour are manganate(vii) ions in aqueous potassium manganate(vii) ?

Answer 6

Purple

Question 7

Why does the mixture turn pink when the reaction is completed?

Answer 7

• Manganate ions react with the reducing agent and I reduced to Colourless Mn2+ ions
• Reaction continues until all the reducing agent has reacted.
• The last drop will give the mixture the pink colour of the oxidising agent