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Chemistry Diagram

'the reaction between hydrogen and chlorine involves two gases with diatomic (two-atom) molecules. The equation for the reaction is: H2(g) + Cl2(g) --> 2HCl(g). Draw two diagrams to explain how increasing the gas pressure will increase the rate of reaction.'
I've searched for this question but can't find it anywhere help pls!
Reply 1
Perhaps one diagram being a container with x particles in it, and the second diagram being a smaller container with x particles in it?
Original post by grindinrevisin
'the reaction between hydrogen and chlorine involves two gases with diatomic (two-atom) molecules. The equation for the reaction is: H2(g) + Cl2(g) --> 2HCl(g). Draw two diagrams to explain how increasing the gas pressure will increase the rate of reaction.'
I've searched for this question but can't find it anywhere help pls!

It is a bit of a strange question and it is far from obvious what it actually wants from you.

If this is an A level question, I’d probably draw something similar to what Methene has described (i.e two pistons compressing a gas mixture with one piston compressing the mixture more than the other), but I’d also make sure to write a sentence along the lines of “higher pressure means less space between molecules, so more frequent, successful collisions between H2 and Cl2.”

If it weren’t asking for a pair of diagrams, I’d probably instead show that pV = nRT rearranges to n/V = p/RT (where n/V is equivalent to the concentration) and so if you change the pressure (at constant temperature), the concentration of gas also increases linearly. I’d then argue (in terms of a rate equation) that this corresponds to an increased rate of reaction.
Original post by UtterlyUseless69
It is a bit of a strange question and it is far from obvious what it actually wants from you.
If this is an A level question, I’d probably draw something similar to what Methene has described (i.e two pistons compressing a gas mixture with one piston compressing the mixture more than the other), but I’d also make sure to write a sentence along the lines of “higher pressure means less space between molecules, so more frequent, successful collisions between H2 and Cl2.”
If it weren’t asking for a pair of diagrams, I’d probably instead show that pV = nRT rearranges to n/V = p/RT (where n/V is equivalent to the concentration) and so if you change the pressure (at constant temperature), the concentration of gas also increases linearly. I’d then argue (in terms of a rate equation) that this corresponds to an increased rate of reaction.

lol i wish it was an A level question then I would have an excuse. I'm in year 9 and got this question for homework, having never seen anything really like it before, but thx, rlly helps :smile:
Original post by grindinrevisin
lol i wish it was an A level question then I would have an excuse. I'm in year 9 and got this question for homework, having never seen anything really like it before, but thx, rlly helps :smile:
God that is a daft question to ask a year 9 lol

Yeah - Methene’s answer is probably best, followed by a sentence like the one I recommended.

The pV = nRT and rate equation thing is more of an undergraduate level concept, so ignore it entirely lol.

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