Equilibrium constant (K) Question problem

[Danny523]

Finding the Equilibrium Constant (K)I have been having a bit of trouble with this question, if anyone could guide me on where I am going wrong it would be greatly appreciated!
"Reaction 1: N2 + 3H2 = 2NH3

Write down an expression for the equilibrium constant K, for reaction 1.
At 25 degrees Celsius the equilibrium concentrations of N2, H2 and NH3 gases are:

N2: 1.3 x 10^-3 mol dm^-3
H2: 1.1 x 10^-2 mol dm^-3
NH3: 9.8 x 10^-1 mol dm^-3

Use these values to calculate the value of K at this temperature"So then what I did was substitute these values into this equation:

K = (NH3)^2 / ((N2) x (H2)^3)

To give this:

K = (9.8 x 10^-1)^2 / ((1.3 x 10^-3) x (1.1 x 10^-2)^3)

That then gave me:

K = 5.6 x 10^8

Im pretty sure that is not right, I am thinking it should be a lot lot smaller...

If you could help me out I would appreciate it a lot!

Thanks

Danny

 

[Borek]

Agreed that value looks high, but that's what you get from the data given.

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