Need help with question 6 as I have only 0.25 and 0.75 as the initial moles of the reactants due to the 1:3 ratio. However, the moles are just 1 and 3. Why is that because I thought the ratio add up to 100%.
That's what I thought but here is the explanation: 'Assuming no product gases (eg NH3) are there to start with (the question hintsat this by saying “left to equilibrate”) we can say that the initial mixture consists of 1 mol of N2(g) and 3 mol of H2(g) as this is the initial ratio'
That's what I thought but here is the explanation: 'Assuming no product gases (eg NH3) are there to start with (the question hintsat this by saying “left to equilibrate”) we can say that the initial mixture consists of 1 mol of N2(g) and 3 mol of H2(g) as this is the initial ratio'
Yeah that's because it's the easiest amounts to deal with. You can use any amount you want though, as long as the 1:3 ratio holds.
You could use 0.0073 mol Nitrogen and 0.0219 mol Hydrogen if you want. That would be stupid, but it would get you the same answer.
You can start with any amount of hydrogen and nitrogen as long as it's a 1:3 ratio. So 1mol of hydrogen and 3mol of nitrogen or 271.5mol of hydrogen and 814.5mol of nitrogen! It does not matter
You can start with any amount of hydrogen and nitrogen as long as it's a 1:3 ratio. So 1mol of hydrogen and 3mol of nitrogen or 271.5mol of hydrogen and 814.5mol of nitrogen! It does not matter
I used 0.25 and 0.75 as my 1:3 ratio. I though for ammonia you just find out 15% of 1 which is 0.15. Thanks
I agree i think but I haven't done this topic before so bare with (I'm going onto 2nd year a level chemistry). n2 + 3h2 --> 2nh3 mole fraction of nh3 = 0.15 mole fraction of n2 = 0.25 - (0.15/4) = 0.2125 mole fraction of h2 = 0.75 - 3(0.15/4) = 0.6375 Pa of nh3 = 1500 Pa of n2 = 2125 Pa of h2 = 6375 Kp = (1500)^2/(2125) x (6375)^3 = 4.08679653e-9 I hope this helps. Happy to explain
Does it consider the change in amounts? Where do they get 6 moles of gas from?
Look at the second question here and its answer, it's basically the same thing but they don't give you a final answer as all of the pressures at equilibrium are unknown:
Does it consider the change in amounts? Where do they get 6 moles of gas from?
Look at the second question here and its answer, it's basically the same thing but they don't give you a final answer as all of the pressures at equilibrium are unknown:
But that question only gives you the partial pressure whereas the question I'm doing now gives you hints about the inital moles and moles at equilibrium here is the explanation
But that question only gives you the partial pressure whereas the question I'm doing now gives you hints about the inital moles and moles at equilibrium
You know there's a 1:3 ratio at the beginning and you know the pressure is 10000kPa. Use this information to draw a table like the one in the example.
You know there's a 1:3 ratio at the beginning and you know the pressure is 10000kPa. Use this information to draw a table like the one in the example.
I have actually done that already but I don't know how to work out the mole of ammonia so my equilibrium moles for the reactants are wrong. If I am using the values 0.25 and 0.75 for my 1:3 ratio, it wouldn't work as 3/2 of 0.9 is 1.35