End point of a titration can be measured in many ways.
Some of which are by using:
- pH indicator: This is a substance that changes colour in response to a chemical change. An acid-base indicator (e.g., phenolphthalein) changes colour depending on the pH.
- A potentiometer can also be used. This is an instrument that measures the electrode potential of the solution.
- pH meter: This is a potentiometer that uses an electrode whose potential depends on the amount of H+ ion present in the solution
- Colour change: In some reactions, the solution changes colour without any added indicator.
Difference between endpoint and equivalence point:
Equivalence Point: Equivalence-point means the moment in your slow, dripping addition,at which the amount of base added is chemically equivalent to the acid in the flask, (or vice-versa) so the two kinds of reagent are exactly cancelling out.
Endpoint: the end-point is the perceptual event at which the indicator actually does change, and you decide you are "done", and you actually read the quantity of measuring reagent you have added. Such as when the solution finally changes colour and does not change back right away.
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Hi Vino,
ReplyDeleteGood try here. Not an easy task to distinguish end point and equivalence point.
Not sure what you mean when you say "the two kinds of reagent are exactly cancelling out"? Please elaborate?
Cheers,
Ms Jee
hello!
ReplyDeletewow I'm still looking for notes on the
Equivalence Point and endpoint haha xD
vino~ i only find meaning for end point and wquivalence point ...= =
ReplyDeleteHello!I think i am so gna update on my blog about this "end and equivalence point" after visiting yours and beenting's blog!haha C:
ReplyDeleteHi vino,
ReplyDeleteJust wondering do we observed the end point or equivalence point when we were doing VA1 practical? :)
by Mr Tan
hey hey!!!
ReplyDeletei updated mine! do comment! :D
so what is the purpose of equivalence point?
RE: Ms Jee,
ReplyDeleteCancelling out means when both the reagents have reacted to form a neutral solution. and there are no excess of either one of the reactants.
This comment has been removed by the author.
ReplyDeleteRE: Mr Tan
ReplyDeletei think we observe endpoint during VA1.