Equilibrium question

Question

Consider the reaction N2O4 (g)---------2NO2 (g).(reversible). If 0.2 is the degree of disassociation , starting with 2.0 moles of N2O4 , the total number of moles at equilibrium would be?

Answer 1

N2O4(g) <===> 2NO2(g)

2.0 mol..............0 mol.......Initial

-0.2*2.0..........+2*0.2*2.0...Change

1.6 mol ........0.8 mol........Equilibrium

Total moles of N2O4 would be 1.6 moles