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Titration evaluation?

Is it possible that for OCR AS chemistry practical we will be asked to evaluate a titration? The only thing I can think of is that it's difficult to pinpoint the moment of neutralisation...

Reply 1

mysteryman

Maybe try wrong sort of indicator used. Colour change is hard to distinguish as i thought thats what you were saying. Maybe is making standard solution one hydroxide used is insoluble?

Reply 2

idiopathic

The titration is practically always better and more accurate than the gravimetric method.

Reply 3

Borek

I don't think so. It is not a problem to weight up to 6 significant digits, while 4 SD is a limit for volume measurements.

Best,
Borek
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Reply 4

idiopathic

My argument was that with gravimetric you usually have to make several measurements -> can lead to cumulative inaccuracy.

Also, the masses you use in the gravimetric method might be very small -> again greater % error.

The titration can have a clear end point colour change, and easier to compare repeats perhaps.

Burettes and pipettes are also well calibrated.

Reply 5

kookabura

Combine two of those replies, if you use the right indicator you should be able to see a clear colour change, but if you use the wrong one then the change wont be that obvious and you might miss it.
Other problems could be with the setting up, if you dont allow the chemical through the tap at the bottom of the burette before taking your first reading it would be inaccurate. People could read it inaccurately, if you dont look at the line on eye level your could get a false reading.

Thats all I can think off - hope it helps.