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# Confused by ideal gas equation question watch

1. An ideal gas occupies 2.75dm3 at 290K and 87000Pa. At what temperature will it occupy 3.95dm3 at 101,000Pa?

So I worked out the number of moles :

n = (2.75x10^-3) x (8.7x10^4) / (8.31 x 290)

n = 0.099277

Then I worked out the temp

t = (1.01 x 10^5) x (3.96 x 10^-3) / (0.099277 x 8.31)

t = 483K

Somehow, the actual answer is 126,000 Pa! Can someone explain this to me? I have no idea why the answer is in Pa when its asking for temp (k)???

thanks
2. I'm equally confused. Are you sure you read the question correctly or the have the correct mark scheme?
3. (Original post by Deliciate)
I'm equally confused. Are you sure you read the question correctly or the have the correct mark scheme?
100% sure. It's even here https://www.thestudentroom.co.uk/sho....php?t=1067588

The answers to the booklet are online and they say 126000 Pa and my teacher did the solutions and posted them on google classroom and got the same as them. I might have to email him tbh,
4. Wow, never come across a question like this before. If you figure out how to do it could you please share it because I'm genuinely curious.
5. I think you are looking at the wrong answer.
6. (Original post by Maker)
I think you are looking at the wrong answer.
I'm not.
7. (Original post by amaraub)
I'm not.
LOL
8. (Original post by Maker)
LOL
aight bigman check it for yourself

task 14 question 13. answers are at the end of the pdf.

http://www.chemsheets.co.uk/Chemshee...substance).pdf

and next time, don't give pathetic feedback like 'you're looking at the wrong answer'. you think i didn't check?
9. yeah the pdf made a mistake. look at the answers to q12 and q13 - they're swapped around. the actual answer for q13 is is 483K. the answer for q12 is 126000pa. it wouldn't make sense for them to ask for the Temperature when the answer should be in pa. don't doubt yourself! textbooks and other resources make errors like this and it totally puts me off studying because it makes me feel like i just keep making mistakes when i'm actually not at all
10. (Original post by amaraub)
100% sure. It's even here https://www.thestudentroom.co.uk/sho....php?t=1067588

The answers to the booklet are online and they say 126000 Pa and my teacher did the solutions and posted them on google classroom and got the same as them. I might have to email him tbh,
Those sheets aren't always correct. It's entirely possible it's a mistake.
11. that's the same booklet our class is using, i know not relevent but wanted to point that out
Also, I did the exact question and got the exact answer and my teacher (who has access to chemsheets) said that they have question 12 and 13 the wrong way round, so your right
12. (Original post by a_d2010)
that's the same booklet our class is using, i know not relevent but wanted to point that out
Also, I did the exact question and got the exact answer and my teacher (who has access to chemsheets) said that they have question 12 and 13 the wrong way round, so your right
Ahhh ok, thanks man
13. Hey i know how to do it firstly you need to know the ideal gas equation PV=nRt you want to look for then temperature so u rearrange the formula to get T=PV/nR temperature should be in kelvin so to get from Celsius to kelvin u add 273 and u subtract to get Celsius

14. Hey the Person who was stuck on the ideal gas equation I solved it btw for those who said the person read the question wrong they didn’t it made sense you just had use what u had to solve the question 😂

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