Answer:
K= 1.25*10⁻⁵ (any of the options) , but if the problem's statement is wrong and D → C, K₂ = [C]/[D] = 2*10³ then K= 8*10¹⁴ (option F)
Step-by-step explanation:
for
2 A + 3 D → 3 C + 2 B
K= [C]³*[B]² /([A]²*[D]³) = ([B]/[A])²* ([C][/D])³
where
2 A → 2 B , K₁ = [B]²/[A]² = ([B]/[A])² =1*10⁵
and
C → D, K₂ = [D]/[C] = 2*10³
therefore
K=K₁* (1/K₂)³=K₁/K₂³ = 1*10⁵ / (2*10³)³ = 1.25*10⁻⁵
K= 1.25*10⁻⁵
but if the problem's statement is wrong and
D → C, K₂ = [C]/[D] = 2*10³
then
K=K₁*K₂³=K₁*K₂³ = 1*10⁵ * (2*10³)³ =8*10¹⁴
K= 8*10¹⁴