Question

5.88 moles of nitrogen and 16.2 moles of oxygen are mixed and heated at 2000C° until equilibrium is established ,11,28 moles of nitric oxide are formed . Calculate the value of equilibrium constant?

Answer 1

I'm assuming a closed system of some volume I'll call L.
.................N2 + O2 ==> 2NO
I.............5.88.....16.2...........0
C..............?.........?...............?
E..............?..........?..............11.28

So ? for 2NO = 11.28. Then 11.28/2 = 5.64 mols O2 and 5.64 mols N2 were used and the table can be redone this way.
.................N2 + O2 ==> 2NO
I.............5.88.....16.2...........0
C.........-.5.64.....-5.64........11.28
E..........0.240.....10.56.......11.28

Do you want Kc. Note that no volume is available so mols/L can't be calculated; however, the volume, whatever it is, cancels in the calculation. Therefore, write the Kc expression, substitute thre E values in mols, and solve for Kc. To be complete, I would substitute 11.28/L, 0.240/L, and 10.56/L for the molarities of each component. Post your work if you get stuck.