The equilibrium constant for thermal dissociation of F2

Question

F2(g)<->2F(g)
is 0.300. If initially 1.00 mol F2 is placed in a 1.00 L container, which of the following is the correct number of moles of F2 that have dissociated at equilibrium?
1. 0.130 mol
2. 0.418 mol
3. 0.548 mol
4. 0.474 mol
5. 0.239 mol
6. 0.176 mol
7. 0.956 mol
8. 0.213 mol

Answer 1

I would like to know if this is Kc or Kp. I will assume Kc and you want to know the x of 1-x although that's a funny way of asking. Perhaps I've misinterpreted the question.
........F2 ==> 2F
I......1.00.....0
C......-x.......2x
E.....1-x......2x