Official AQA AS Chemistry Unit 1 - 23Rd May 2013

But I'm pretty sure (correct me if I'm wrong), the question stated, "in terms of intermolecular forces"

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Ah, well that makes sense then :smile:

Reply 981

wbrian

can somebody kindly give me a link to the unit 1 23rd june 2013 edexcel as chemistry thread

Reply 982

Rooroo96

4

Grade boundary predictions anyone? Will 54/55 be an A? :'( this was such a bad exam, for people who did it in January... Do you think it was worse?

Reply 983

AimHigh27

Original post by mynameisntbobk

For the first part, both OH groups are attached to the end carbon.. what class does that make it? (The carbon is also bonded to 1 C and 2 Hs)

Second part, you want a ragent that will convert OH(alcohol) to =O(aldehyde) to COOH(carboxylic acid). One I'd go for is either acidified potassium dichromate or acidified potasium manganate

Final part, treat [O] as an oxygen molecule..
CH2(OH)CH2CH2CH2(OH) + 2[O] -> HOOCCH2CH2COOH

Thank you, that makes sense now. So it would be primary class, because only attached to one carbon right? Thank you :yes:

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Reply 984

Mr__H

Original post by Rooroo96

Grade boundary predictions anyone? Will 54/55 be an A? :'( this was such a bad exam, for people who did it in January... Do you think it was worse?

I think it is generally going to be around that mark, 54-58 being around an A grade, just my opinion, I thought it was an easy paper, apart from the maths bit which was a bit tricky.

Reply 985

Rooroo96

4

Can someone please help me?!?!?? :'( for ALL the calculations questions, I had the absolute correct method but for some stupid reason I can not comprehend right now, I used the proton number (30) instead of the mr (65.5) for zinc. So even though my method was correct, I just used the wrong mr, how many marks will I get? The problem is I did this mistake for all three qns, I used 30, will I get ECF??? Please someone help me, I feel like killing myself right now!!! Such a stupid mistake

Reply 986

marth34

7

Original post by Rooroo96

Grade boundary predictions anyone? Will 54/55 be an A? :'( this was such a bad exam, for people who did it in January... Do you think it was worse?

I thought January was far more straight forward. With the calculations, in Jan they were quite generic (standard textbook ones), whereas I felt you needed to apply your knowledge a lot more for the maths part of this one.

Reply 987

marth34

7

Original post by sophie phil

yeah, but in asthma, it is harder for the person to exhale and inhale during respiration therefore, carbon is toxic as it causes asthma

You might have got the mark if you said it triggers asthma (what causes asthma is a different story) or if you said it can lead to a lung condition. However, it's not technically toxic just because it can lead to these conditions, but I doubt the chemistry examiner will mind.

(and breathing is different from respiration)

Reply 988

CHEM AND BIO TIME!

13

DAM IT I WROTE THAT CARBON IS POISONOUS

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Reply 989

Thebest786

2

I wrote it causes global dimming. Will that get the mark?

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Reply 990

mynameisntbobk

18

Original post by AimHigh27

Thank you, that makes sense now. So it would be primary class, because only attached to one carbon right? Thank you :yes:

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yep

Original post by Thebest786

I wrote it causes global dimming. Will that get the mark?

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it doesn't cause global warming, it contribuutes to it..

Reply 991

Thebest786

2

Cause or contribute. Mentioning global dimming, will that do it, as I've seen in some mark schemes global dimming is accepted.??
:redface:

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Reply 992

Rooroo96

4

Original post by marksmith34

You might have got the mark if you said it triggers asthma (what causes asthma is a different story) or if you said it can lead to a lung condition. However, it's not technically toxic just because it can lead to these conditions, but I doubt the chemistry examiner will mind.

(and breathing is different from respiration)

Hi there, you seem to really know your chem! Do you remember a question that roughly went ' why is the second ionisation energy of carbon higher than the first?' Havent seen it ln the markscbeme, Was the answer just a simple response about the 2nd IE being removed from a positive ion and is more strongly attracted etc? Or did it have to be specific to carbon? I think I mentioned something about doubling up in an orbital, can't remember grrr . . Also how many marks do you think I could get on all the moles qns if I had absolute correct method but stupidly used 30 as the Ar of zinc ach time :'(