11-Finding amount Of Iron In Tabley Via Redox Titration

Question 1

Describe method in CP11 = finding mass of iron in iron tablet via redox titration with manganate

Answer 1

1- record mass of tablet
2- crush tablet and dissolve in sulphuric acid + Filter
3- Make standard solution - must be dissolved in acid not water
4- Titrate Potassium manganate against solution ( KMnO4- Purple)
5- Stop titration at pink colour

Question 2

What happens in the redox titration between potassium manganate and Iron in CP11

Answer 2

Once all Iron in sample has been oxidised = nothing lest to reduce the Manganate Irons = Purple colour shows

Question 3

Why can only Dilute Sulphuric acid be used in the titration of potassium manganate against Iron - CP11

Answer 3

Other acids set up alternative Redox reactions
= insufficient volume of Sulphuric acid used will mean solution is not acidic enough = MnO2 will be produced instead of Mn2+