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Chemistry: Acid/bases

Hello,
I have been doing Acid/bases chapter,there's one thing I couldn't get which is why do we take aqueous solutions in titration,I means why can't we take calcium oxide however,aqueous solution of calcium oxide is used.
thanks .

Reply 1

Daisy87!

When they’re in aqueous solution, the acid/bases Ions are able to fully dissociate.

Reply 2

abdullahAK

glad that someone replied,but Daisy if opt the other way around how it would be different?Thanks a lot.

Reply 3

Daisy87!

Original post by abdullahAK

glad that someone replied,but Daisy if opt the other way around how it would be different?Thanks a lot.

What do you mean by opt?

Reply 4

abdullahAK

I mean if we simply use for instance"Calcium oxide rather than its aqueous solution " will it not work when using titration method?

Reply 5

Daisy87!

Aqueous solution simply refers to the state of the compound or element. Aqueous solution is needed for a titration rather than solid. You can still use calcium oxide but it’s state symbols will be (aq) not (s)

Reply 6

abdullahAK

Oh,it means it works both ways.
Thanks for your really "quick" replies.

Reply 7

Mr.noname

Original post by abdullahAK

Oh,it means it works both ways.
Thanks for your really "quick" replies.

Suppose if it was solid how do plan to use it in a burette ? Where as for aqueous solutions can can use it in the burette or flask.
The primary reason why most acid base titration require aq solutions is because strong acids (almost) dissociate fully so in the case of HCl it will exist as H+ and Cl- and for HNO3 it will exist as H+ and NO3-. So for a strong base e.g. NaOH which also protonates to Na+ and OH- in solution the two reactions that will occur are:
Cl- + Na+ -----> NaCl (formation of salt)
OH- + H+------->H2O (formation of water)
Similarly for another strong acid like HNO3 water is still formed in the same way but just a different salt:
NO3- + Na+ -----> NaNO3 (formation of salt)
OH- + H+------->H2O (formation of water)
So if you use a solid base or acid in titrations the compound will first dissolve in the solution of the other compound then it will react with it in ionic state, for an accurate process like titration you want everything to happen instantly so you get the closest possible value to the true value.