The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

OCR Chemistry F322 June 2016

Scroll to see replies

Original post by nicoleemmak
When you drew the structure of the fragment peaks did you have to put + signs???


yep i think u do, i got 1 h2c=chch2+ and other one i forgot.
Original post by Saywhatyoumean
Also I got -281 for the enthalpy question I think I did something wrong :/


Posted from TSR Mobile


I got that too
Reply 62
Avatar for mattyk5
mattyk5
2
Original post by cyborgom
yep i think u do, i got 1 h2c=chch2+ and other one i forgot.


was it not ch3chch2+?
Carbon was like 32percent or whatever. Divide that buy 100 x 150 = 48
48/12 = 4
And I got overall mr as 136.9
What was the mass of excess magnesium ?

I got 0.302 something like that

25% + mass of magnesium no?


But my mates said it was 25% + mass of the other metal which gave the mass of excess magnesium
Original post by mattyk5
was it not ch3chch2+?

im not sure....:confused::confused::confused:
i thought it was quite a fair paper just didnt like the petrol question ...and didnt get to finish the last 2 mark question as ran out of time but other than that thought it was quite good :smile: did anyone else run out of time ?
Original post by leobrave
Carbon was like 32percent or whatever. Divide that buy 100 x 150 = 48
48/12 = 4
And I got overall mr as 136.9

i think they said less than 150
Reply 68
Avatar for mattyk5
mattyk5
2
Original post by cyborgom
im not sure....:confused::confused::confused:


no sorry youre right, i just got confused. I got the same as you :smile:
Original post by leobrave
Carbon was like 32percent or whatever. Divide that buy 100 x 150 = 48
48/12 = 4
And I got overall mr as 136.9


You work out the molecular formula straight away which was c3h7br , I'm pretty sure that's what I got
Reply 70
Avatar for mattyk5
mattyk5
2
Original post by mercuryman
What was the mass of excess magnesium ?

I got 0.302 something like that

25% + mass of magnesium no?


But my mates said it was 25% + mass of the other metal which gave the mass of excess magnesium


yh i did 25% of the mass and then add it on. So i got like 0.31 (2 decimal place because it said it had a 2dp weighing scale or something)
(edited 7 years ago)
Original post by mattyk5
no sorry youre right, i just got confused. I got the same as you :smile:

thank god:h:
But which mass ???

that's what I'm baffed about lol

Surely it was mass of mg right?
Original post by mattyk5
yh i did 25% of the mass and then add it on
Reply 73
Avatar for mattyk5
mattyk5
2
Original post by mercuryman
But which mass ???

that's what I'm baffed about lol

Surely it was mass of mg right?


yes mass of Mg
Original post by mercuryman
What was the mass of excess magnesium ?

I got 0.302 something like that

25% + mass of magnesium no?


But my mates said it was 25% + mass of the other metal which gave the mass of excess magnesium

Would you not have done moles of the other thing x125 then worked out the mass from that
Original post by mattyk5
was it not ch3chch2+?


I FORGOT THE +!!!!! NOOOOO...think i will still get 2/3 marks?
What do we think the boundary for an A grade will be?
Reply 77
Avatar for mattyk5
mattyk5
2
Original post by bakedbeans247
I FORGOT THE +!!!!! NOOOOO...think i will still get 2/3 marks?


yh i think you lose one mark for the "+"
I worked out 25%of the moles of mg, then added it to original moles of mg and then worked out the mass of it.
Original post by bakedbeans247
I FORGOT THE +!!!!! NOOOOO...think i will still get 2/3 marks?


I'm pretty sure I've seen this in a mark scheme, so 2/3 I'd say for sure.

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you