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OCR F321 January 13th 2012 Draft Mark Scheme

Thanks to AladdinSane94 who kindly uploaded the paper. I have gone through all the questions and answered them as best as I could, but please don't take this as a 100% accurate mark scheme it is a draft. There are bound to be mistakes, differences in opinion etc. please post if you have any suggestions. I am only a student, so if any teachers are able to scan through this to check for accuracy it would be much appreciated, any comments welcome.

(edited 12 years ago)

unofficial chem mark scheme jan 13 2012.doc37.9KB

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Reply 1

Amscared

1 (b) (ii) Not sure "Iodine is toxic" is sufficient, id expect answers to be somthing more along the lines of ethical issues.

2 (b) Its a carbonate but it is not MgCO3, we know that its a calcium solid so its Calcium Carbonate CaCO3

2 (e) Anybody else feel that this question was possibly the worst ever seen on a paper, its so subjective. The answer could just as easily be "because he was blind" or "because he didnt study chemistry"

3 (a) (i) You may lose marks for using the term "holding", orbitals dont hold 2 electrons they are simply the region were they are located.

Reply 2

james1234190

Ok, MS updated.

Any more comments much appreciated - this is a work in progress.

(edited 12 years ago)

Reply 3

Neuro Alex

Pretty good nice work, for 4b the relative bond strengths probably need to be mentioned 1000, 50 etc though I definitely forgot to say that!

iOS this for OCR A?

Original post by Alex Bampton

Pretty good nice work, for 4b the relative bond strengths probably need to be mentioned 1000, 50 etc though I definitely forgot to say that!

Will add those in now, thanks for the suggestion.

Reply 6

james1234190

Original post by ieatcheeseyo

iOS this for OCR A?

Yes, this is for the F321 paper.

Reply 7

ieatcheeseyo

Original post by james1234190

Yes, this is for the F321 paper.

Ok cheers, I done OCR B Salters

I was like... "Got that one wrong then...and that one"
Then I realised :L

Reply 8

james1234190

Original post by ieatcheeseyo

Ok cheers, I done OCR B Salters

I was like... "Got that one wrong then...and that one"
Then I realised :L

Hope your exam went well.

Reply 9

elanor95

wouldn't NaClO name be bleach? :frown:

Reply 10

elanor95

for the KI one at the start it said about the radioactive isotope, so I put it could contain that isotope?! is that a stupid answer? :')

Reply 11

otrivine

Original post by james1234190

Ok, MS updated.

Any more comments much appreciated - this is a work in progress.

Thanks

would they accept hydrogen as weak van der waals cause they are present in everything?

Reply 12

inspiredideas

i think h20 is an open latice because they asked specifically about ice

Reply 13

Dan12

for 4c) the Mr of potassium is 39.1 not 39.2 so I think the answer is 72.00 cm3

Reply 14

otrivine

Original post by inspiredideas

i think h20 is an open latice because they asked specifically about ice

so will they not accept weak van der waals?

Reply 15

inspiredideas

i think they wanted hydrogen bonds but im not an expert

Reply 16

otrivine

Original post by inspiredideas

i think they wanted hydrogen bonds but im not an expert

and for suggest one i said unhealthy can cause cardiovascular diseases ?

Reply 17

inspiredideas

i completely guessed that one i put iodine is poisonous maybe they wanted something about how pottasium reacts with water ?

Reply 18

otrivine

Original post by inspiredideas

i completely guessed that one i put iodine is poisonous maybe they wanted something about how pottasium reacts with water ?

if you get marks between 38- 43/44 is there a possible of an A grade cause JAN 2011 WAS 44 AND THIS HAD MORE CHALLEGNING QUESTION S?

Reply 19

james1234190

Original post by elanor95

wouldn't NaClO name be bleach? :frown:

Quite possibly, I thought that question was somewhat ambiguous as to whether they wanted the systematic, or common name. I will add to the mark scheme though, that is a valid answer.