For the reversible reaction, X2g⇋2Xg carried out in a one litre closed vessel, the number of moles of reactants and products at equilibrium are equal. Degree of decomposition of X2g is

X2g⇌2XgInitial moles                               1             -      Moles at equilibrium             1−α         2αGiven, at  equilibrium   1−α=2α                                            α=13                                            α=0.33