Posted by Frank on .
Given: N2O4 (g) « 2NO2 (g) @ 25 degrees celcius, Kc is 5.84 x 10^3.
(A) Calculate the equilibrium concentrations of both gases when 4.00 grams of N2O4 is placed in a 2.00 L flask at 25 degrees celcius.
(B) What will be the new equilibrium concentrations if the volume of the system is suddenly increased to 3.00 L at 25 degrees celcius.
(C) What effect would increasing the pressure at 25 degrees celcius have on the equilibrium?

CHEMISTRY HELP NEEDED A.S.A.P 
Dr Russ,
You have not shown the units for Kc, but let us assume that the units are moles/L
1. Calculate the number of moles of N2O4 and hence the concentration (C) in moles/L.
2. At equilibrium let the concentration of NO2=x
Thus Kc=[NO2]^2/[N2O4]
Kc=(x)^2/(Cx)= 5.84x10^3
we know C so solve for x
for part B repeat the calculation using the new volume.
for part C by Le Chateliers Principle the equilibrium will move in the direction to accommodate the change so will move to smaller volume, which is the N2O4 side.