Potassium 23.5g/39.0983g/mol = 0.601mol
The Ratio of reactants is 2 to 1 so (0.601mol)/2 = 0.3005mol
Therefore 0.3005mol of F2 is needed to find liters use
formula V = nRT/P (V)Volume = 22.41L
(T)Temperature = 273K or 0.0 Celsius
(P)Pressure = 1.0atm
(R)value is always .08206 with atm n = 0.3005moles (273)(.08206)(0.3005)/1 = V V = 6.7319 Liters