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

Hmm, I liked the June 2010 paper and that was pretty low boundaries like 71 for an A. I think something like that would be good.

Dont even mention F324 haha . I'm gonna have to cram like crazy on wednesday evening and thursday.

Same here, i really liked June 2010, whereas Jan 2011 . As long as theres no big marker on a calculation, but knowing my luck there probably will be . I havent looked at it since easter if im honest, im putting it off cus' i think i'll do ok on that one, but hey i might just end up crying the night before .

I need some general help with noticing what state symbols to use for equations >< . FOr example, there was a question which asked me to write down the full and ionic equations for some acid-base reactions, including:
1) Hydrochloric acid and solid calcium carbonate
2) Nitric acid and magnesium oxide

1) Easy enough, acid is obviously (aq) and CaCO3 was stated as (s).
2) Acid is (aq) but they didn't actually 'state' the state for Magnesium Oxide, so it got me there.. I took a guess that it was solid, but how do I know for sure? If it were aqueous I would have had the entire answer wrong!

This has probably been asked on here 100 times, but does anyone have the A2 exam cafe answers from the book? Our school doesnt give us the cds

Hmm, I liked the June 2010 paper and that was pretty low boundaries like 71 for an A. I think something like that would be good.

Dont even mention F324 haha . I'm gonna have to cram like crazy on wednesday evening and thursday.

Haha i'll join you with the cramming!!!! I have psychology on the 21st so spending the 6 days doing psychology. done absolutely nothing 'cos im too traumatized about biology and chemistry.. after 21st its major cramming! Ive done benzene (first topic).. quite proud.

when do you not need to use a platinum catalyst?

can someone also explain to me ionic size and charge for lattice enthalpies with examples please?

Hi,

I was working through a pack of questions from my teacher on unit 2. The question was from jan 2009 trends and patterns (old spec) past paper and I'm not sure if she has accidently included it or if my answer is wrong for a reason:

The question is: Explain why magenesium carbonate decomposes at a much lower temp than barium carbonate.

My observation is that magnesium and barium have the same ionic charge but barium has a greater ionic radius than magnesium and therefore the electrostatic attraction between oppositely charged ions in the magnesium is greater as the ionic radius is smaller so ions pack closer together.

Therefore I would think that you would need more energy, and hence a higher temperature to break down the ionic lattice which is stronger (magnesium) and not less temperature as the question suggests.

Is this just a case of an old question including concepts that we don't need to know about or am I making an error.

I hope we don't need to know that either it comes up loads in the legacy spec and I don't really understand it , check this out it helps a bit.
http://www.chemguide.co.uk/inorganic/group2/thermstab.html

Just marked the specimen paper... Hate it with a passion! This paper is so finicky with the wording. I guess I just have to learn to read the effing question!!

There are so many mistakes in the specimen paper. And our paper is not going to be like that at all. There is hardly any application in that paper.