Measuring water hardness, question 1 (1 Viewer)

[NizDiz]

The quantity of Chloride ions in a water supply can be determined by titration of a sample with silver nitrate solution. A 10 ml sample of bore water requires 24.7ml of a 0.0100 mol/L silver nitrate solutin to react completely with all the chloride ions present.

a) write a balanced net ionic equation for this reaction.
b) calculate the no. of moles of Cl ion in the 10.0 ml water sample.
c) determine the mass of chloride ions present in the 10.0 ml water sample.

Wasn't sure whether to use 10 mL in b), put I didn't. If so, why not?

I got 8.76 mg, can someone claify this for me.

Thanks All help greatly appreciated!

 

[kostadalianas]

your answer is correct, you do not use 10ml in your calculations, you find concentraion of silver ions by n=c*v, the volume has to be of the AgNO3 solution (this is because all the moles of silver are in the 24.7 ml solution) , as it is a 1:1 stociometric ratio there is an equal amount of Cl- moles and thus you simply then multiply by Cl's atomic mass