[lexi105]

Hi again,

I'm just trying to finish up this chemistry course and am doing it through correspondence, so I don't have a teacher to ask myself. For this reason I have a couple more questions. I have attempted to figure out this question but am unsure about the correctness of my answers. Any help would be greatly appreciated. Thanks!

The formation of products is strongly favoured in this acid-base system:HX + B- <=> HB + X-
a) Identify the bases competing for protons.
B- and X-

b) Which base is stronger?
B-

c) Which is the weaker acid, HX or HB?

HB

d) Does the K for this system have a large or small value?
I'm not quite sure how to find this.

e) How is the equilibrium affected by the addition of the soluble salt NaB?
 Is NaB a buffer solution?

[Dan]

The formation of products is strongly favoured in this acid-base system:HX + B- <=> HB + X-
a) Identify the bases competing for protons.
B- and X-

b) Which base is stronger?
B-

c) Which is the weaker acid, HX or HB?

HB

Correct

d) Does the K for this system have a large or small value?
I'm not quite sure how to find this.

You are told that the formation of products is strongly favoured. Write out the expression for the equilibrium constant. Do you think that K>1 or K<1 ?

e) How is the equilibrium affected by the addition of the soluble salt NaB?
 Is NaB a buffer solution?

This is Le Chatelier's principle. Note that NaB is a soluble salt.

[jennielynn_1980]

I am doing the same question and I am also trying to figure out part e) how the equilibrium is affected by the addition of NaB. The only thing I can think of is that adding NaB would again favour the formation of products because the B would be available to bond with H and the Na may bond with X-.  Is this on the right track?

[DevaDevil]

Think of Le Chatelier's principle:
If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change.

Now, if you would add B- to the solution what would happen to the equilibrium if this disturbance is to be counteracted?

PS. Ignore the Na⁺ as the sodium will be in solution, remember what Dan said: NaB is a soluble salt.