[poonilization]

http://i.gyazo.com/7fdf2ebcfdc0161c59258241f1964db4.png

I'm not sure how to answer party iv) in this question, any help would be appreciated.

The only thing i can think of is going across the period the atomic radii decrease in size. So Ti is a larger atom than Ga, Ti forms longer and weaker bonds compared to Ga, therefore its easier to break those bonds and lose the oxygen.

But i dont think it's that simple. There must be more to this question.

[mjc123]

The question asks about thallium, not titanium. Basic piece of advice, always read the question carefully!
What do you know about the relative stability of the N and N-2 oxidation states going down a group?

[poonilization]

Oh gosh, you're right i need to read questions more carefully!

Is this question to do with the inert pair effect? Tl prefers to form the +1 oxidation state so will readily loses oxygen on heating to go from +3 to +1 oxidation state.
Ga favours +3 oxidation state and therefore doesn't lose oxygen on heating.


Edit: never mind that doesn't make sense , just having a look through my notes to see if i can find something to answer this question.

Ok to answer your question, as you go down the group the stability of the N-2 oxidation state increases. So in this case, Ga prefer +3 oxidation state, however as you go down the group, Tl prefers the +1 oxidation state.

[unsu]

Tl prefers to form the +1 oxidation state so will readily loses oxygen on heating to go from +3 to +1 oxidation state

Same happens to lead: 2PbO₂  2PbO + O₂ (heating)

Ga prefer +3 oxidation state, however as you go down the group, Tl prefers the +1 oxidation state.

This is correct. Now try to explain what causes the relative "inertness" of the 6s² electrons. Compare the chemical properties and stabilities of Tl, Pb, Bi with the other elements in the corresponding groups.