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?

See above

To solve this problem, we need to use the given equilibrium constant (Kc) and the balanced equation for the reaction. Let's go step by step:

(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 Celsius.

1. First, we need to convert the mass of N2O4 to moles. The molar mass of N2O4 is 92.02 g/mol.
Number of moles of N2O4 = 4.00 g / 92.02 g/mol = 0.04346 mol

2. Since the balanced equation shows that 1 mol of N2O4 produces 2 mol of NO2, we can calculate the number of moles of NO2 produced.
Number of moles of NO2 = 2 x 0.04346 mol = 0.08692 mol

3. To determine the initial concentration of N2O4, we divide the number of moles by the volume of the flask.
Initial concentration of N2O4 = 0.04346 mol / 2.00 L = 0.02173 M

4. Similarly, the initial concentration of NO2 can be calculated:
Initial concentration of NO2 = 0.08692 mol / 2.00 L = 0.04346 M

(B) What will be the new equilibrium concentrations if the volume of the system is suddenly increased to 3.00 L at 25 degrees Celsius.

Since the volume of the system increases, the concentrations of the gases will decrease according to the increase in volume. The molarities (M) of both gases will decrease by a factor of (2.00 L / 3.00 L) = 2/3.

New equilibrium concentration of N2O4 = 0.02173 M x (2/3) = 0.01449 M
New equilibrium concentration of NO2 = 0.04346 M x (2/3) = 0.02898 M

(C) What effect would increasing the pressure at 25 degrees Celsius have on the equilibrium?

According to Le Chatelier's principle, increasing the pressure will shift the equilibrium in the direction that produces fewer gas molecules. In this reaction, the forward reaction (N2O4 to 2NO2) produces two molecules of gas, while the reverse reaction (2NO2 to N2O4) produces one molecule of gas. Therefore, increasing the pressure will shift the equilibrium to favor the reverse reaction, resulting in a higher concentration of N2O4 and a lower concentration of NO2.