A student titrated an aliquot of standard sodium carbonate solution with hydrochloric acid in a burette. State whether the concentration determined for the hydrochloric acid would be likely to be higher, lower or unchanged compared with the actual value if the student had previously washed with water, but not dried, the following apparatus:

a) the pipette used to deliver the aliquot of sodium carbonate solution

b) the flask containing the aliquot

c) the burette.

 

Any help to the above questions would be immensely appreciated!

What would any extra amount of water do to the concentration of w/e solution you are putting in there?

What would any extra amount of water do to the concentration of w/e solution you are putting in there?

 

 

It would dilute the concentration of the solution. However what do you mean by "w/e"?

 

What's the logic behind the question?

 

I want to know particularly for future reference. It sounds like a typical exam type question.

 

For question c, if there is water left over in the burette from a previous washing with water it would dilute each titre and as a result require a slightly greater amount of recorded HCl to be used in the titration. For it to react and reach the stochiometric mole ratio, more recorded HCl, in litres, will be used. But still not seeing the logic.

For question c, if there is water left over in the burette from a previous washing with water it would dilute each titre and as a result require a slightly greater amount of recorded HCl to be used in the titration. For it to react and reach the stochiometric mole ratio, more recorded HCl, in litres, will be used.

 

You just answered the logic behind my question with this. Ie. not dried means that some water remains. And you answered what happens after that with the above quote.

 

w/e means whatever

Edited March 30, 201114 yr by Fuzzwood

You just answered the logic behind my question with this. Ie. not dried means that some water remains. And you answered what happens after that with the above quote.

 

 

but would the recorded concentration of HCl be lower, higher or unchanged...and how would you know?

Still not getting it...

i mean i know that the the HCl in the burette would be more diluted and hence be of lower in concentration but would this be the recorded concentration for HCl?

Edited March 30, 201114 yr by gerald_mcdonald