Question

A student ran the following reaction in the laboratory at 327 K:

CH4(g) + CCl4(g) 2 CH2Cl2(g)

When she introduced 4.07E-2 moles of CH4(g) and 7.57E-2 moles of CCl4(g) into a 1.00 Liter container, she found the equilibrium concentration of CH2Cl2(g) to be 1.21E-2 M.

Calculate the equilibrium constant, Kc, she obtained for this reaction.

Answer 1

I suggest you find and use the arrow key. Since the volume is 1L, the # mols = concn in M.
.......CH4(g) + CCl4(g)==> 2 CH2Cl2(g)
I.....0.0407....0.0757.........0
C.......-x.........-x.........2x
E......0.0407-x..0.0757-x.....2x
The problem tells you 2x = 0.0121M
That allows you to calculate the E line for each constituent. Substitute those values into Kc expression and solve for Kc. Post your work if you get stuck.