[campycalire]

I have just nearly done my plan and wondering if:

0.2 moldm-3 of NaOH and 0.1mold dm-3 of HCL are appropiate concentations to use? and if they would work? and if I used less conecntration of HCL as it is a 1:1 relationship I have to assume that twice as much acid is required?
Thanks
Claireb

[campycalire]

Also is magnesium sulphate , MgSO4 a solid?
Claire

[sjb]

I have just nearly done my plan and wondering if:

0.2 moldm-3 of NaOH and 0.1mold dm-3 of HCL are appropiate concentations to use? and if they would work? and if I used less conecntration of HCL as it is a 1:1 relationship I have to assume that twice as much acid is required?
Thanks
Claireb

The concentrations seem fine, and I can't see any real problem with the neutralisation occuring with them. Be careful what you're saying, however. You will still need the same amount of acid to neutralise the NaOH regardless of the concentration (to a very good approximation), but if you use a less concentrated solution the volume of solvent will be greater.

Also is magnesium sulphate, MgSO4 a solid?
Claire

Yes.

[campycalire]

Thank you
O so saying if I pippete 25cm3 of NaOH into a flask I have said to make sure fill the burrette with at least 50cm3 of HCL in order to make sure that reaction is complete? Shall I not say a amount?
Thanks
Claire

[Arkcon]

Assume the concentrations are completely correct, and determine, by calculation, what volume that adds up to.  Then look at the graduations on your receiving flask.  If the liquid level is too low, you might not notice the end point.  You shouldn't titrate to more than half fill a flask, at the very most.

[campycalire]

Sorry I am not totally sure on what you are saying to do?
Thanks
Claire

[Arkcon]

25 ml of 0.2 M NaOH requires what volume of 0.1 M HCl to neutralize?  If the volume of the two liquids mixed are bigger than your flask, you will have to start over.  If they add up to a volume almost as high as your flask, or a height of 1 cm up from the bottom of the flask, you will not be able to see the endpoint clearly.

[campycalire]

Ok thank you, are you sure that if I have decided to use 0.2 mol dm-3 of NaOH it might be more suiatble to use 0.2 mol dm-3 of HCL or is using 0.1 mold dm- 3 ok? Not totally sure? As the 0.2 mold -3 of caus is an approximate value due to the fact it has been diluted from an aproximate value of 2 mol dm-3 concnetration
Thanks Claire
xx

[wilson]

Ok thank you, are you sure that if I have decided to use 0.2 mol dm-3 of NaOH it might be more suiatble to use 0.2 mol dm-3 of HCL or is using 0.1 mold dm- 3 ok? Not totally sure? As the 0.2 mold -3 of caus is an approximate value due to the fact it has been diluted from an aproximate value of 2 mol dm-3 concnetration
Thanks Claire
xx

I do not quite understand what you are trying to say. Why are you picking concentrations in a titration? Isn't a titration meant to determine concentrations?
The thing here is that you have to choose your analyte's volume such a way that the total volume at the end-point does not go more than half the volume of the flask, or worse, over the flask's capacity.

[campycalire]

I aint picking the titrations, it is becuase I have got a plan for my exam and I have been given approximate value of NaOH which is 2 mol dm-3, and I have to find the actual value of the NaOH, for this reason I have chosen to dilute the amount so its an approximate 0.2moldm-3 value, hence why I have chosen 0.1mol dm-3
get me now?
Thanks
Claire