AQA GCSE Chemistry Paper 2 Unofficial Markscheme (Higher) - Triple - 12/06/19

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Reply 20

Maximus 190

Original post by JoshWalters

i got 1250cm3

How?

Reply 21

JoshWalters

I used the formula mol=cm3/24000 to find the moles of c02 which was 0.15 then divided it by 3 to find the mol of one portion then times it by 5 to find the mol of oxygen then use the same formula to find the volume of oxygen. The volume was 6000cm3 then you do 7250-6000 to get 1250cm3

Original post by Khyake

do you remember how you did it?

Reply 22

Erevising45

I got the same but I don’t think it’s right either! 😂
Apart from that question, overall I think it was a good paper. Went well for me!

Original post by imogen28

I got 2886.4 for the volume but I’m not convinced that’s right :lol:

Reply 23

mannylozano123

Wait so is the answer 1250cm^3 Thags what I got or is it 750?!

Reply 24

Ellen bennett

Original post by imogen28

I got 2886.4 for the volume but I’m not convinced that’s right :lol:

That’s what I got as well 😂

Reply 25

MAXW303

If you used 24, you’re assuming they’re at room temp and pressure, but you are using moles as well, so I think it’s 1250

Reply 26

GLvet1092

I got 750 ? How did you guys get 1250 ?

Original post by Maximus 190

I got 1500?

Original post by MAXW303

1250 for volume or 750?

Reply 27

JoshWalters

What did everyone get for the rate between 2 and 4 minutes?

5.5

Spoiler

Original post by MAXW303

Or , I’d did
7.25*3/5=4.35
4.35-3.60-=0.75dm^3
=750cm^3

Reply 30

Duwang

Do you think I'll get the mark if I put the names of the test instead of describing what you had to do?

Reply 31

Safzal0332

Original post by MAXW303

5.5

same

Reply 32

MaliciousFlower

did minutes instead of seconds on rate of reaction mean ughhhhh

Reply 33

imogen28

Original post by Erevising45

I got the same but I don’t think it’s right either! 😂
Apart from that question, overall I think it was a good paper. Went well for me!

The only thing making me think it’s not is that they didn’t give the RAMs which is what I used for it so I don’t think that was what I was meant to do 😂 Otherwise it was good though! Although that’ll increase the grade boundaries even higher than they normally are for chemistry 😫

Reply 34

1st superstar

share you answers guys and how did you do

Reply 35

mannylozano123

5.5 is wrong cause u had to convert 2 minutes into 120 seconds it was something like 0.092

Original post by Safzal0332

same

1.25 unburned ??

Original post by Safzal0332

same

For the rate between 2 and 4 minutes?
i got 0.65cm3/s for that

Reply 38

Hattyfalcus

Balancing the equation?

Reply 39

Maximus 190

I did this;

3.6mol / 24 (molar gas constant) = 0.15 mol

0.15 mol * 5/3 = 0.25 mol of oxygen
0.25 * 24 = 6 dm^3
So 1.5 dm^3 spare
1.5*1000 = 1500cm^3