You are Here: Home

# EDEXCEL UNIT 2 (RESIT) 2016 Answers Watch

1. Pretty sure the iodine value was ~80.6g
2. (Original post by ToxicPhantom007)
The number of moles you got is right. Though they asked that thses moles are in 0.2 g of oil so in 100 g of oil we had to multiply moles by 500 and the moles came were 0.45 something
0.45 x 2(126.9)= 114.8 g
80 is wrong
Wasn't the moles 0.3 or something tho?
3. (Original post by Hdb)
Pretty sure the iodine value was ~80.6g
I reckon so
4. (Original post by RUNSran)
Oh I get it .. do you think i will the marks that follows if i carry my error forward?
ECF would definitely apply so you've lost maybe 1/2 marks max on that calculation.
5. I got 107
6. (Original post by Crespo0008)
I reckon so
Everyone apart from 1 person I know got that value lol! It was more of a unit 4 calculation haha
7. What did everyone get for the very last question about the sample and iodine-would it increase, decrease or neither?
8. (Original post by mayaham12)
What did everyone get for the very last question about the sample and iodine-would it increase, decrease or neither?
Increased titre, lower iodine value.
9. How did people explain what was going in step 1 and 2 of the thermal decomposition of Mg(NO3)2
10. (Original post by corpeal)
How did people explain what was going in step 1 and 2 of the thermal decomposition of Mg(NO3)2
Thought water would come out in step 1, then it would turn to steam in step 2 after enough heating.
11. (Original post by RUNSran)
yeah i got something similar - dont know how people got 80 something. What was the moles of s203 that reacted in the blank titration?
0.004 moles? i don't remember exactly
what did you get? ^_^
12. (Original post by scrlk)
Increased titre, lower iodine value.
same
13. Does anybody know the value of the concentration calculation in the multiple choice?
14. i got 0.3725 or something like that i cant remember fully
15. (Original post by beanigger)
i got 0.3725 or something like that i cant remember fully
0.001-0.000365=0.000635, 0.000635x500=0.3175
126.9x2x0.3175=80.58g
16. (Original post by Hdb)
Does anybody know the value of the concentration calculation in the multiple choice?

0.33
17. Hey I have 3 questions about section A
What was the 1st answer? I put C (3)
What was the conc of na2s04? I guessed and put 0.5
What was organic molecule using wave number And? I out the aldehyde one
Ty guys
18. (Original post by corpeal)
How did people explain what was going in step 1 and 2 of the thermal decomposition of Mg(NO3)2
Step 1: I assumed that some of the Mg(OH)2 had precipitated out of the solution and that upon heating its solubility increases and so dissolves back into it.

Step 2: Water was evaporating and CaO was being formed via thermal decomposition
19. (Original post by Kaka121)
Hey I have 3 questions about section A
What was the 1st answer? I put C (3)
What was the conc of na2s04? I guessed and put 0.5
What was organic molecule using wave number And? I out the aldehyde one
Ty guys
Yeah first one I put C too,
I put 0.33 for the concentration.
And I take it you mean the IR spectra, where I also put the aldehyde.
20. (Original post by JoeyTr)
Yeah first one I put C too,
I put 0.33 for the concentration.
And I take it you mean the IR spectra, where I also put the aldehyde.
Ohh ok are you sure C was right?! And how did you get 0.33?
Lastly did you also get 0.4 for uncertainty? I think I got 19/20 in section A hopefully

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: June 11, 2016
Today on TSR

### Am I pregnant?

...or just paranoid?

### Top study tips for over the Christmas holidays

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.