Answer:
Writing a balanced Equation for the reaction
Br₂ + 3Cl₂ ==> 2BrCl₃
Kc = [BrCl₃]² / [Br₂][Cl₂]³
Each Concentration (n) = moles/volume of container.
(nBrCl₃)= 1/6 = 0.167moldm-³
(nBr₂) = 2/6 = 0.333moldm-³
(nCl₂) = 6/6 = 1moldm-³
Kc = (0.167)² / (0.333)(1)³
Kc = 0.0838.