At a certain temperature and total pressure of 105 Pa, Iodine vapour contains 40% by volume of I-atoms.I2(g) ⇌ 2I(g) Calculate Kp for the equilibrium,

Given, I-atoms in iodine vapour  =  40% by volumeMole fraction of I atoms = 40100I2 Molecules inIodine vapours = 60% by volumeMole fraction of I2= 60100Partial pressure of I-atomsp1=40100×105=4×104 PaSimilarly, partial pressure of iodine molecules I2,p2=60100×105=6×104 PaKp=pI2pI2=[4×104] 2[6×104]=2.67×104 Pa