Edexcel Official Chemistry Paper1:Core Inorganic and Physical Chemistry - 27th of May

I forgot to mention lattice structure! But wrote all about the bonding and electrical conductivity and high melting pint, this okay?

As long as you mentioned the fact that the boiling and melting point is affected by the strength of the electrostatic attatction between the delocalised electrons and the metal atoms, and the fact that there are delocalised electrons which can carry the charge, then you're fine :smile:

Reply 181

Promethean_M

6

Ah that makes sense, as last year they had some coursework so it was less per written exam

Reply 182

Glparker123

How many marks do you reckon for at least a C?

Reply 183

clairebear101

11

Yeah I did exactly that! Thank you :smile:

Reply 184

richpanda

16

Original post by Glparker123

How many marks do you reckon for at least a C?

I'd guess about 47 marks. It's hard to know because it's a new specification.

Reply 185

schmitz.

For the polar bonds question - Q1, 2nd page- were they asking about the polar bonds in CLF3 or CIF3?

I read it as the latter, and so talked about the C-I non-polar bond, and the C-F polar bond, but I've heard from friends that what I mistook to be an 'I' (for iodine) is actually an 'L' (for chlorine).

Just wondering if I was blind and completely misread the compound, and, if I talked correctly about the polarity of the bonds with a reason, whether I should be able to salvage a mark? Thanks

Reply 186

clairebear101

11

I misread it as Chlorine :frown:

so upset and hope I get some marks still :frown:

it was probably CI

Reply 187

username1893177

8

Original post by clairebear101

I misread it as Chlorine :frown:

so upset and hope I get some marks still :frown:

it was probably CI

I'm pretty sure it was chlorine

Reply 188

Cryptokyo

14

I am pretty sure it is chlorine because it was an inorganic paper and a compound with carbon is organic. Furthermore, compounds with carbon are not commonly referred to using molecular formulae and it would be called iodotrifluoromethane. I don't think edexcel are trying to trick us by using similar symbols. Chlorine triflouride does exist.

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Reply 189

richpanda

16

Agh that's playing on my mind now- I read it as Cl (chlorine) bonded to F3. However it could have been C I F3 (carbon iodine and flourine). The problem is that lower case L and upper case i look the same. Not very clever from edexcel, should have tried to avoid any confusion.

I expect that there will be about a 50/50 split in those who read it 1 way or the other. When things like this happen, the chief examiner will often amend the marking criteria if lots of people write correct answers, but couldn't identify what the question was asking.

Reply 190

richpanda

16

Original post by Cryptokyo

I am pretty sure it is chlorine because it was an inorganic paper and a compound with carbon is organic. Furthermore, compounds with carbon are not commonly referred to using molecular formulae and it would be called iodotrifluoromethane. I don't think edexcel are trying to trick us by using similar symbols. Chlorine triflouride does exist.

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It was still stupid of them though, but I also did it as chlorine trifluoride. Wasn't the question asking about the bond polarities? What did you put? I said that the bonds would be polar due to electronegativity difference, and that Cl would be delta positive as it is less electronegative. I also quoted the Pauling values from the data book.

Reply 191

Cryptokyo

14

Original post by richpanda

It was still stupid of them though, but I also did it as chlorine trifluoride. Wasn't the question asking about the bond polarities? What did you put? I said that the bonds would be polar due to electronegativity difference, and that Cl would be delta positive as it is less electronegative. I also quoted the Pauling values from the data book.

The question was about bond polarities and I did the same as you and compared electronegativity to show that it was a polar bond.

Reply 192

Florent venhari

9

It was definitely Chlorine. It was an inter-halogen of Cl and F, which formed a Distorted T shape if you drew it out (but that bits not important) :smile:

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Reply 193

Florent venhari

9

Original post by richpanda

It was still stupid of them though, but I also did it as chlorine trifluoride. Wasn't the question asking about the bond polarities? What did you put? I said that the bonds would be polar due to electronegativity difference, and that Cl would be delta positive as it is less electronegative. I also quoted the Pauling values from the data book.

I spoke about it being an unsymmetrical shape, therefore the bond polarities wouldn't cancel out, so it is a polar molecule. ?

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Reply 194

Shk

I dont think the question was about the overall molecule polarity just about the individual bond polarity

Original post by Florent venhari

I spoke about it being an unsymmetrical shape, therefore the bond polarities wouldn't cancel out, so it is a polar molecule. ?

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Reply 195

Florent venhari

9

Original post by Shk

I dont think the question was about the overall molecule polarity just about the individual bond polarity

Well, the question was 3 marks, so two would be for the definition, so I could get the last mark if it is accepted in the mark scheme, but if not, oh well :smile:

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Reply 196

sc67

Has anyone made or started making an unofficial mark scheme for this paper ?

Reply 197

username1893177

8

Original post by richpanda

Agh that's playing on my mind now- I read it as Cl (chlorine) bonded to F3. However it could have been C I F3 (carbon iodine and flourine). The problem is that lower case L and upper case i look the same. Not very clever from edexcel, should have tried to avoid any confusion.

I expect that there will be about a 50/50 split in those who read it 1 way or the other. When things like this happen, the chief examiner will often amend the marking criteria if lots of people write correct answers, but couldn't identify what the question was asking.