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# Difference between s.t.p and r.t.p in chem

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1. basically^
2. bunp
3. pls

I dunno, brah. I hope that helps though.
5. bump
6. (Original post by sfaraj)
bump
I did chemistry and what exam board is this? Can you ask the question in full your more likely to get a response.
7. (Original post by Epistemolog y)
I did chemistry and what exam board is this? Can you ask the question in full your more likely to get a response.
OCR
CaCO3 + 2HCL -> CaCl2 + H20

what mass of marble is needed to give 11g of CO2 and what vol will this occupy in s.t.p
8. (Original post by sfaraj)
OCR
CaCO3 + 2HCL -> CaCl2 + H20

what mass of marble is needed to give 11g of CO2 and what vol will this occupy in s.t.p
ah OCR sucks lol. Doesn't seem that hard still don't know what s.t.p means though lol. What have you learned in school? My chemistry a bit rusty but I think you need to use molar ratios and the who mole = mass / mr. So 11g / 44 (the relative atomic mass of C02) then you would use molar ratio? Is that the complete question? I am quite intrigued now. Respond and we can work on it together.

edit: pv=nrt? this is getting me worried oh wait I have realised it (I think) wait...

edit2:
CaCO3(s) + 2 HCl(aq) --> CaCl2(aq) + CO2(g) + H2O(l)
so as I was saying number of moles = mass in g / mr so 11/44 (Mr of C02) will give you amount of moles. then after you get that you use the molar ratio of 1:1 as CaCO3 is marble. Then you multiply that by the MR of CAC03 and you should have it in grams.
9. (Original post by Epistemolog y)
ah OCR sucks lol. Doesn't seem that hard still don't know what s.t.p means though lol. What have you learned in school? My chemistry a bit rusty but I think you need to use molar ratios and the who mole = mass x mr. So 11g / 44 (the relative atomic mass of C02) then you would use molar ratio? Is that the complete question? I am quite intrigued now. Respond and we can work on it together.

edit: pv=nrt? this is getting me worried oh wait I have realised it (I think) wait...
aha thank you!!

stp= standard temperature pressure

right now we're doing gas volumes questions tbh.

i get the mole to pascals equation. but idk what stp is. i know rtp
10. (Original post by Epistemolog y)
ah OCR sucks lol. Doesn't seem that hard still don't know what s.t.p means though lol. What have you learned in school? My chemistry a bit rusty but I think you need to use molar ratios and the who mole = mass / mr. So 11g / 44 (the relative atomic mass of C02) then you would use molar ratio? Is that the complete question? I am quite intrigued now. Respond and we can work on it together.

edit: pv=nrt? this is getting me worried oh wait I have realised it (I think) wait...

edit2:
CaCO3(s) + 2 HCl(aq) --> CaCl2(aq) + CO2(g) + H2O(l)
so as I was saying number of moles = mass in g / mr so 11/44 (Mr of C02) will give you amount of moles. then after you get that you use the molar ratio of 1:1 as CaCO3 is marble. Then you multiply that by the MR of CAC03 and you should have it in grams.
to the best of my knowledge that seems correct. but after that step you need to work out the volume of gas at standard temperature and pressure of which i dont know
11. ah yh OCR is harder and im not used it. You use PV=nRT you have all of the variables you just rearrange for V meaning you get nrt/P .

P is in pascals im assuming you would use 100,000 P t would be in kelvin (273 +degrees) but I thought it would be at room temperature so you add 25 degrees but google is saying differently. R is constant at 8.31 if I remember correctly. What a silly question but I hope I helped a little
12. (Original post by sfaraj)
to the best of my knowledge that seems correct. but after that step you need to work out the volume of gas at standard temperature and pressure of which i dont know
So are we done?

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