[CIE alevel]

Please summarize what is to be done in this titration activity. I'm lost with the calculation part too!! I really need to understand what is been asked as this type of question will come in my exam. So please help with this QUESTION OF:

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Please give me tips on the practical front.

[Borek]

www.titrations.info for some information about practical part and titration theory. Otherwise your question is too broad. Once you will have have specific questions - we can help.

[CIE alevel]

Ok so. I have a doubt on the practical part of this:

Dilution of FA 1
By using a burette measure between 38.00 mL and 39.00 mL of FA 1 into the 250 mL
graduated (volumetric) flask labelled FA 3.
Record your burette readings and the volume of FA 1 added to the flask in the space
below.
Make up the contents of the flask to the 250 mL mark with distilled water. Place the
stopper in the flask and mix the contents thoroughly by slowly inverting the flask a
number of times.

1) Doesn't a 250mL graduated (volumetric) flask look like this:


2)Do I to keep the graduated (volumetric) flask under the burette and then run FA1 from burette into the flask???..

**If so then, its quite unpractical to put the above flask under a burette which will need to be pulled up high so that its extremely above eye level to read initial volume.

...Or just run FA1 into a beaker & then transfer the amount to a graduated (volumetric) flask???

[Borek]

**If so then, its quite unpractical to put the above flask under a burette which will need to be pulled up high so that its extremely above eye level to read initial volume.

Good point, but...

Or just run FA1 into a beaker & then transfer the amount to a graduated (volumetric) flask?

This can be tricky - you have to be sure you have transerred all solution from the beaker to the graduated flask - this is not trivial, as even traces of the solution in the form of film on the glass surface mean additional source of error. You can wash the beaker three times with distilled water and transfer it all to the flask, but it can be tricky (splashing, losing solution and so on). Transfering directly to the flask is a better idea, even if it is technically difficult.

[CIE alevel]

Hey Borek, thanks for the quick reply 

This can be tricky - you have to be sure you have transerred all solution from the beaker to the graduated flask - this is not trivial, as even traces of the solution in the form of film on the glass surface mean additional source of error. You can wash the beaker three times with distilled water and transfer it all to the flask, but it can be tricky (splashing, losing solution and so on). Transfering directly to the flask is a better idea, even if it is technically difficult.

Ha I thought so!! ye i guess, in volumetric analysis doing even some transferring can cause loss of measured volume.

Are u sure the said graduated (volumetric) flask looks like the above image/
Given that I'm avg. high school guy height,I will hav to use a stool to reach  eye level of burette!!

My next doubt says: Do i have to draw up a table to record burette readings and the volume of FA 1 like this?:


The examiner reports say that volume to dillute a chemical is recorded with rough,1,2 readings. Isn't that a waste of time??

Whats the point in doing that as the vol of FA1 needs to be between 38.00 & 39.00 mL ?
Is it not enough to just take 1 reading of initial volume (e.g 4.10mL) and adding:
4.10 + 38.5  = 42.6 mL which can b quickly titrated as final volume ?

I mean i already know whats needed. They r saying just measure between 38.00 & 39.00 mL so i can use any 1 volume in that range, right???