Firstly, I prepared a standard magnesium sulphate solution 500 ml of 0.1M. This required exactly 12.3245 g.
I titrated EDTA against 20 ml of this standard solution (with 10 ml of ammonia buffer and a few drops of indicator) to determine the concentration of EDTA.
Then used this EDTA of known concentration and titrated it against 20 ml of ‘dissolved battery’ solution (with 10 ml of ammonia buffer and a few drops of indicator).
All reactions are 1:1.
This is how the battery bit was done:
"A NiCad battery solution has been prepared for you, where, 161.3975 grams of NiCad batteries have been dissolved in dilute acid, filtered, and then quantitatively made up to a volume of 25 litres."
[EDTA] = 0.11
[Ni] = 0.03