Equilibria, Energetics and Elements (F325) - June 2011 Exam.

what is the tetrahedral complex and what are the bond angles?

Susan did you get my message earlier?

Reactions involving Complex ions:

- Percipitation
- Substitution
- Redox

Any more?

half a mole of acid reacts with half a mole of a base this then forms it's conjugate base and water, but when using a whole mole of acid and half a mole of base half a mole of acid doesn't react and forms a buffer with the half mole of it's conjugate base

WHAT THE ****!!! I DIDNT KNOW THAT!! looooooooooooooooooool

so what happens to the other half of the acid then??? reacts to form water?

Bond angle of square planar?

I'm confused, when deltaG<0, the reaction is spontaneous and hence stable, but in the mark scheme of the jan 11 paper it says deltaG>0 is stable. Why is this?

A buffer solution is a solution of a weak acid and its conjugate base. It finds its own equilibrium depending on conditions. This is the acid disassociation constant, Ka.


HA (aq) <--> H+(aq) + A-(aq)
Ka =
[H+][conjugate base (represented by A-]
----------------------------------------------------
[Acid(represented by HA)]

When a small amount of acid is added the concentration of H+ increases. The equilibrium position shifts to the left, as the conjugate base reacts with MOST of the H+ ions to form the initial acid on the left hand side of the disassociation equation above.
When a small amount of an alkali is added concentration of OH- increases. MOST of these react with H+s already in the solution to form H2O, and more HA disassociates to restore pH

THIS!

Octahedral - 90 degrees bond angles.

What are the bond angles for tetrahedral and square planar?

Any chance you could give us the reactions, or tell us where to find them? Please.

im sorry whaaat?

I'd learn the whole mess regarding thiosulfate titrations and the colour changes there, I have a hunch it might come up