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can someone help me with this As Chemistry Kc question?

In an experiment, 9.0 moles of nitrogen and 27 moles of hydrogen were placed into a vessel of volume 10 dm3 and allowed to reach equilibrium. It was found that two thirds of the nitrogen and hydrogen were converted into ammonia. Calculate Kc for the reaction.
N2(g) + 3H2(g) ==> 2NH3(g).

Reply 1

Donthebest

I don’t understand how to do mole ratio with kc and how to sirt out rhe moles on the left and right...... seriously don’t know how to do these harder ones. If anyone can help i will be greatful 👍

Original post by Donthebest

Reply 2

Levi23317

Well 2/3 were converted into ammonia, so this leaves you with 3 moles of nitrogen and 9 moles of hydrogen. And since the nitrogen to ammonia ratio is 1:2, this will give you 12 moles of ammonia (as 6 moles of nitrogen were converted, so it will make 12 moles of ammonia). Then you divide each by 10 (as 10dm^3 container) to get the concentrations, so you can put them into the Kc equation.