Fluorine reacts with oxygen to yield oxygen difluoride.

2 F2(g) + O2(g) 2 OF2(g)K = 2.00x 10^2

(a) Calculate [O2] at equilibrium when [OF2] = 0.25 mol/L and [F2] = 0.0208 mol/L.
mol/L

(b) Calculate [OF2] at equilibrium when [F2] = 0.088 mol/L and [O2] = 0.513 mol/L.
mol/L

You need to FIND and USE arrows; how are we to know where reactants stop and products begin?

Are these values INITIAL? or equilibrium?