What's the answer for hsc2005 q's 27? (1 Viewer)

[AngelBunny`]

Can someone give me the answer to hsc2005 q's 27? I don't understand the graph at all

Why the concentraition of reactants and product do not change between T1 and T2? if the molar concentraition of hydrogen and nitrogen decrease, shouldn't the ammonia molar concentraition decrease as well?

 

[toadstooltown]

At T1 the system reaches equilibrium so that the rate for forward reactino equals the rate of the backawards reaction. Therefore, the concentrations of each chemical remain the same as they're being created and destroyed at the same rate. At T2 when the size of the vessel is decreased, there's the same amount of chemicals so that their molar concentration (I assume it's moles per litre or something) increases, as we're packing more into that tight space. Yet, increased pressure will also shift the equilibrium to the right, as there are less gas molecules and hence less pressure. So that the concentratinos of H and N will spike, but then start to get less and less while NH3 will continue to go up a bit. Importantly, eventualy it reaches equilibrium again and they become flat lines.

 

[AngelBunny`]

Oh... so that's what it means... Thank you!