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AQA - Unit 5 - Energetics, Redox and Inorganic Chemistry

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It was an okay paper, easier than the Jan 2011 but I was very disappointed with the lack of questions on colours of ions. Only one 3 mark question right at the end. Lots of questions on electro chemical cells and periodicity stuff. Need a C in this paper and judging by people's reaction, the grade boundaries might be higher this time around. Well at least I can relax for a month and a half now. Exams done, dreading results day :angry:

Reply 1521

Willyg11

Tricky first page....

Reply 1522

happi_minnie

is the paper up anywhere or will it go up anywhere? I just want to guess how much marks i roughly got right....

Reply 1523

Zakir

Original post by Willyg11

i put KNO3(s) +H20(l) ---> HNO3(aq) + KOH(aq) :s only one mark anyway....

Original post by Scaudwell

I'm fairly sure it's just KNO3 (s) ---> K+(aq) + NO3-(aq)

what was the answer to the question after that...

why delta S was positive??

Reply 1524

Mij786

just teseting how good my memory is. there were 8 questions. The paper was ok, not mega hard or really easy. was a fair paper tbh.
Q1 was the enthalpy of formation, hydration, interactions of F- with water. then there was the enthalpy of solution whcich gave you the hydration and LF values.

then they had the mean bond enthalpy of forming one mole of ammonia and the part 2 was to say why it isnt an accurate value.
there was the KN03 + water Q
and explain why the product is more stable (increase is S from react to products)
then ur average G= H -TS Q forming one mole of ammonia.
was it feasible?
what happens to the value of G as temp is decreased
what type of reaction is it at the new temp?
periodicity
was Mg and O2 what is seen and type of bonding
same with S and O2
again with Na20 and water and why does is it alkaline

aluminoum oxide experiment to show ions
the one reason Q. then the thin layer is added to prevent oxidation

Aluminium oxide and 6HCL equation
Aluminium oxide and 2NaOH and 3H20
Q4

Reply 1525

jamest92

Original post by Zakir

what was the answer to the question after that...

why delta S was positive??

Said aqueous ions are less ordered than solid ions

Reply 1526

Zakir

Original post by jamest92

Said aqueous ions are less ordered than solid ions

oryt...

i put there are more product particles than reactant particles (got it from the june 2010 mark scheme)

Reply 1527

Scaudwell

Original post by Zakir

oryt...

i put there are more product particles than reactant particles (got it from the june 2010 mark scheme)

You might get away with it. I think as long as you make reference to there being more molecules produced, which is favourable in terms of entropy.

Reply 1528

Zakir

Original post by Scaudwell

You might get away with it. I think as long as you make reference to there being more molecules produced, which is favourable in terms of entropy.

hmmm...thanks!

thats one mark in the bag, at least! :tongue:

Reply 1529

freya(:

Hi i didn't divide by 2 in the ammonia question. Do you think i'll lose one mark or more? It seems a little unfair that they would penalise me in other questions for just one mistake... If someone could clear this up it would be much appreciated as alot of people have been asking. Thanks! :smile:

Reply 1530

strawberry_cake

Wow!! This threads going crazy now! I started readin through the comments but theres too many ;p

Hmm, some bits really made me think like those emf cell graphs.., I read through the cgp batteries and uses topic this morning ony so I hope what I've written is right :/

I walked out of the exam and remembered that I forgot to write the colour for the last question :mad:

I didnt divide by 2 for the mean enthalpies, didnt know what delta E meant, had no idea about the ionic equations :frown:

..id never even seen howto do them and attempted several times then ended up writing thr normal ones. And I've made some more silly mistakes and guessed a few bits but i think it was arite overall :smile:

What do people think grade bondaries will be? And unofficial mark scheme anyone?? :biggrin:

Reply 1531

KissMyArtichoke

Original post by Scaudwell

You might get away with it. I think as long as you make reference to there being more molecules produced, which is favourable in terms of entropy.

I wanted to put that, but I think some of them were ions? I know how picky they can be about using the right word.

Reply 1532

Mikkels88

Original post by Zakir

oryt...

i put there are more product particles than reactant particles (got it from the june 2010 mark scheme)

that depends on your equation, i thnk the point was there was the same number or particles, one was solid and one aqueous, so you are saying that aqueous ions are more disordered than solids

Reply 1533

Mikkels88

also, for testing Al203 ions, could you put react with NaOh to make NaAl(OH)4 and hten dissolve that in water, and the solution would conduct electricity and therefore contain ions?

ridiculous question

Reply 1534

strawberry_cake