measuring pH of identical concentrations of strong and weak acids (1 Viewer)

[persephone]

i think my class used a pH probe, but what are we supposed to gain out of it?

do we have to show that identical concentrations don't necessarily mean the same pH?

or is there something that i'm not getting

 

[helper]

A strong acid completly ionises. A weak acid only partialy ionises so will have a higher pH for the same concentration

 

[mercury]

Example

0.2M of HCl and 0.2M of CH3COOH would have different pH, as one is a strong acid (dissociates completely), the other is a weak acid (about 1% dissociation).

Further suppose you have two acid solutions of equal volume, A and B, both of pH 2.53. You will not be able to conclude which is the stronger acid, because you don't know the concentrations of these two solutions.

 

[nit]

Mercury...are you Shannon?

Edit: by the way, what are you doing lingering around these boards anyway?

 

[mercury]

i'm here to serve the community