Unofficial Mark Scheme CHEM2 June 2013 COMPLETED

Please I'm stressing out so much guys please help me what would 81/100 get me in terms of ums

Reply 181

Original post by tilownii

Please I'm stressing out so much guys please help me what would 81/100 get me in terms of ums

Because I need 106 to get a B overall help me guys ASAP thank u very much :redface:

Reply 182

propagation

14

Original post by tilownii

Please I'm stressing out so much guys please help me what would 81/100 get me in terms of ums

No one knows that it depends on the average marks overall. But it should defiently be an A

Reply 183

Original post by propagation

No one knows that it depends on the average marks overall. But it should defiently be an A

Thank you. I hope it is anyway because I need 106 to get a B as I screwed it up in my chem 1 and isa so just praying its a good A like 115 ums or so :biggrin:

thanks once again xxx

Reply 184

OP

I just added it up and got 98/100. Slightly biased since I wrote the mark scheme? Probably so haha.

Reply 185

OP

Original post by tilownii

Thank you. I hope it is anyway because I need 106 to get a B as I screwed it up in my chem 1 and isa so just praying its a good A like 115 ums or so :biggrin:

thanks once again xxx

In terms of UMS the paper is out of 140

Reply 186

Original post by Danny-r

In terms of UMS the paper is out of 140

Yeah I know lol :smile:

thank u very much and let's hope u get an A or full ums as that's what most people want and also hope that I get a good A if I get 81/100 lol thank u xx

Reply 187

OP

Original post by tilownii

Yeah I know lol :smile:

thank u very much and let's hope u get an A or full ums as that's what most people want and also hope that I get a good A if I get 81/100 lol thank u xx

I've got an A, I couldn't be more certain, but this is my second shot at it after getting a D last year. Found it very easy this year, the whole year, I got an A on unit 1 too. I'm just hoping to get a high UMS mark to drag my A2 grade up. I'm at a C in A2 so hopefully I can get a grade good enough to get a B overall.

Reply 188

Original post by Danny-r

In terms of UMS the paper is out of 140

What do u predict the grade boundaries are for this paper? I'm thinking like 79 or 80 to get an A as everybody seems to have done amazingly well but some silly mistakes lol which could put the grade boundaries down by a bit :biggrin:

not mean it in a bad way for people that haven't done so well

Reply 189

5bii) Doubt reflux will get a mark it's either decrease the temperature or use aqueous conditions
10aii) Need to say increase in CONCENTRATION not "number of molecules" as the number of molecules in the equation won't change

Also draw repeating unit of monomer you don't need brackets

Reply 190

OP

Original post by 1029384756

5bii) Doubt reflux will get a mark it's either decrease the temperature or use aqueous conditions
10aii) Need to say increase in CONCENTRATION not "number of molecules" as the number of molecules in the equation won't change

Also draw repeating unit of monomer you don't need brackets

Operating under reflux is a requirement for nucleophilic substitution to be favoured. If it increases the temperature then proportionally you'll have the same amount, if you run it under reflux the majority will be X.

Reply 191

Original post by Danny-r

Operating under reflux is a requirement for nucleophilic substitution to be favoured. If it increases the temperature then proportionally you'll have the same amount, if you run it under reflux the majority will be X.

But decrease temp is still right though?

Reply 192

For the scrap iron question I wrote uses less energy/ saves energy would this give me a mark? And the other question I have is that I wrote warm aqueous as this is what nucleophilic substitution needs doesn't it?

Reply 193

Huragok

Original post by WavingFLag

Can I suggest an edit?
The last question asked for Mg with oxygen which is MgO
Then it specified Mg with COLD water which is MgO + H2
Mg reacts with STEAM to make Mg(OH)2 + H2
And then it asked what is a medicinal use for one of its reactions - I can't remember the exact question - and that referred to Magnesium hydroxide which is used to neutralise excess acid.

I don't think you know what you're talking about.

Reply 194

OP

Under reflux was a shot in the dark for me. Decreased temperature could be right although I think in reality (which exams aren't) it wouldn't have a massive effect unless you first changed the conditions to suit nucleophilic substitution.

Reply 195

Original post by Danny-r

Under reflux was a shot in the dark for me. Decreased temperature could be right although I think in reality (which exams aren't) it wouldn't have a massive effect unless you first changed the conditions to suit nucleophilic substitution.

Textbook says temp and solvent

Reply 196

Huragok

There's no C(triple bond)N. Just C-N as far as I'm aware.

Reply 197

Original post by Huragok

There's no C(triple bond)N. Just C-N as far as I'm aware.

Definitely triple bond

Reply 198

OP

Original post by Huragok

There's no C(triple bond)N. Just C-N as far as I'm aware.

Then answer the following questions and you'll realise that you've made a basic GCSE error.

How many electrons in carbons outershell?
How many bonds can carbon therefore make?
Was it a carbocation?
Now go and look at a datasheet on the AQA past papers website and realise your error.

Reply 199