will titration be on hsc paper? (1 Viewer)

[misanthropy]

lol packing it right now.. im gonna fail this chem exam 2morrow for sure but i want to atleast do well im 1 section atleast.. i dont know.. anyways umm will titration be on the paper?
coz im my trial paper we done titration other than the electives shipwrecks etc.. we done a paper on titration.. anyways.. yeah will it be on the paper 2morrow?

 

[rumour]

The calculations in many papers came from titrations, so it prolly will be in the exam!!!

 

[beta-omega]

lol, we havn't seen the paper, so how will we know??? haha, there most probably be titration, either calculations, or the procedure, or both... GOOD LUCK GUYS!

 

[misanthropy]

okie dokie thanks..

 

[misanthropy]

well i meant if it will likely be on there.. i wasnt assuming that u guys knew for sure..
lol

good luck to all that has chem 2morrow..
even with luck i wont pass..

 

[xeriphic]

also titration curves

 

[Managore]

I hate titration can someone recap on where the acid goes and where the base goes? or does it change?

 

[Paroissien]

Titration curves... refresh my memory please

 

[lucyinthehole]

acid in the burette, base in the flask. rince the burette and the pippette with their respective things. flask just rinsed with water.

 

[Paroissien]

Solution of known concentration goes in the burette, and the solution of unknown goes in the conical flask

 

[lucyinthehole]

Titration curves... refresh my memory please

uh... i'll try to find a pic of an example, but basically they show the change in the pH throughout the titration. they go flat, suddenly verical, then flat again. they often have questions where you have to pick the appropriate indicator. you want the indicator to have its range in the part where the curve is vertical. the curves vary according to whether it's a strong-strong or strong-weak titration

here

 

[lucyinthehole]

Solution of known concentration goes in the burette, and the solution of unknown goes in the conical flask

lol, yes, that's more correct. i was a bit limited in my answer, just thinking of the ones we usually do. also, with reference to titration curves, if you put the base in the burette, the curve is like reversed or something, ie starts at the top, rather than the bottom of the pH scale

 

[wind]

Strong acid + strong base = equivalence point at ph 7
Strong acid + weak base = equivalence point at ph < 7
Weak acid + strong base = equivalence point at ph > 7

Strong acid + strong base graph:
http://img.photobucket.com/albums/v194/wind_/titration_curve_s-s.gif

 

[rumour]

acid in the burette, base in the flask. rince the burette and the pippette with their respective things. flask just rinsed with water.

Not always, they can be the other way you know

EDIT:
Can someone tell me what indicator is used when the eq. point pH is near 7?

 

[Paroissien]

Ahh. That's all the graphs are. I can do that

 

[lucyinthehole]

Can someone tell me what indicator is used when the eq. point pH is near 7?

phenopthylene (sp?) i believe

 

[rumour]

Isn't phenolphthalein used for basic pHs?

Or are you talking about another indicator?

 

[beta-omega]

bromothymol blue

 

[lucyinthehole]

Isn't phenolphthalein used for basic pHs?

Or are you talking about another indicator?

possibly...

 

[mathock]

nooooo.... base goes in the burette, its a lot easier... when trying to find an unknown base, use the equation

ml x M = ml M


and manipulate the equation to make the ukown molarity the subject, so it should look liek this-->

M(base) = [ ml(acid) x M(acid) ] / ml(base)

the best method is base in the burette and using phenolphthalein... the solution will go from clear to pink, a lot easier than if the base is in the erlenmeyer flask, because the solution would go from pink to clear and the intermediate point would be near impossible to find... hope that helps