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AQA GCSE Combined Triology Chemistry Higher paper 2 12 June 2019 unoffical markscheme

For the mole question i had 7.8×10^4 instead of 0.002, as the text was asking for the moles of copper and not the mole of the molecule containing copper. I've just calculated the percentage of relative mass of copper present in the compound. Then I've multiplied the %(around 39%) to 0.002.

Tell me if I'm wrong pls

Reply 41

username4746572

17

I said it would shift right (forward ) to make more product as it concentration decreases on product side

Original post by Georgiax71x

I put equilibrium shifted to the left due to equilibrium wanting to reduce change and therefore shifting to the one with most moles.

Reply 42

username4746572

17

No clue sorry :frown:

Original post by Valentino299

For the mole question i had 7.8×10^4 instead of 0.002, as the text was asking for the moles of copper and not the mole of the molecule containing copper. I've just calculated the percentage of relative mass of copper present in the compound. Then I've multiplied the %(around 39%) to 0.002.

Tell me if I'm wrong pls

Reply 43

lehcar2qb

6

i put 0.008 as my answer but then crossed through it and wrote something else. do u think they’d look past it and give a mark?

Reply 44

Aamilah.m

For the moles question I put 2g for the answer do you think I’ll still get 2/3

Reply 45

1st superstar

OP

22

why did you merge my thread it's soo confusing and i am not even written as the thread starter

Original post by Evil Homer

I've merged a few threads trying to sort a markscheme out so you are all together :smile:

Reply 46

Georgiax71x

8

Some of the chemical was removed.
This would reduce the moles.
Equilibrium would want to minimise that change and shift to where there were most moles as they had been removed.
This would mean to the left where there was more.

That is basically what o said

Original post by THE-BLACK-CAT

I said it would shift right (forward ) to make more product as it concentration decreases on product side

Reply 47

A.J_MURAPPR

9

Original post by Georgiax71x

I put equilibrium shifted to the left due to equilibrium wanting to reduce change and therefore shifting to the one with most moles.

Moles didn't have anything to do with that question, since it was talking about SO3's concentration, not pressure. You're right on the equilibrium part tho

Reply 48

username4746572

17

That’s what I thought :smile:

Original post by A.J_MURAPPR

Moles didn't have anything to do with that question, since it was talking about SO3's concentration, not pressure. You're right on the equilibrium part tho

Reply 49

mixhelleee

13

Original post by THE-BLACK-CAT

I said you do evaporation cause even tho PH might be 7 it can still be not pure

I said the boiling point , pure water has a fixed boiling point

Reply 50

Lazaursq

4

What did y’all get for the answer to the calculating the solid in the 100cm^3 river

Reply 51

Lucastead

2

Original post by Georgiax71x

For water test, first 2 marker
Drop of water into universal indicator paper. Turns green if it has a pH of 7 and is pure.

Purity of water is if it boils at exactly 100 celcius, many things are completely neutral

(edited 4 years ago)

Reply 52

mm7046

2

yup same, but some people got 0.0031 or smth like that for the moles one, i got 0.002 tho so

Original post by scarlettbx

Same i got those answers too

Reply 53

ec2308

5

No I don’t think that’s right because it had to shift to the left to more reactant particles would react therefore increasing the products

Reply 54

EliteWhovian

16

Anyone else get 7.81g for one of the first maths questions?

Reply 55

london503

1

I hope so because thats what I put

Original post by Aamilah.m

For the moles question I put 2g for the answer do you think I’ll still get 2/3

Reply 56

mm7046

2

idk i put that the sun emits short wavelength radiation and when it gets into the atmosphere, the gas molecules don't strongly interact with the short wavelength radiation. but when the earth absorbs the radiation, it's reflected out as long wavelength radiation as infrared?, and the gas molecules strongly interact with the long wavelength radiation, causing the greenhouse gases to absorb the infrared radiation, and because the gases are trapped, it heats up the atmosphere

Original post by Lazaursq

What did y’all get for the answer to the calculating the solid in the 100cm^3 river

Original post by Georgiax71x

Last 4 marker this is as far as I got.
Sun is emitted as short wave radiation. It is absorbed as long wave infra red radiation. This is then absorbed by greenhouse gases, causing the earth to warm and the greenhouse effects. Things such as ice clads melting and a disruption in migration patterns are a result of this.

Reply 57

Ollywmoor

3

Original post by THE-BLACK-CAT

post your answers ! ^^
Percentage question - 8.8%
Moles question - 0.002 (2x10^-3)
Last calculation question - 15 g

The moles one isn’t 0.002, that’s the moles of copper sulfate NOT just copper which was needed in the question, the answer instead is 0.000796

Reply 58

Ollywmoor

3

I got the same, no one else seems to have read the question properly where it says moles of COPPER and not COPPER SULFATE

Original post by Valentino299

For the mole question i had 7.8×10^4 instead of 0.002, as the text was asking for the moles of copper and not the mole of the molecule containing copper. I've just calculated the percentage of relative mass of copper present in the compound. Then I've multiplied the %(around 39%) to 0.002.

Tell me if I'm wrong pls