Consider the gas-phase reaction of ethylene (C2H4) with hydrogen (H2) to form ethane (C2H6), which occurs in the presence of a palladium catalyst.

Write a balanced equation for this equilibrium. Do not include the palladium catalyst. Include all physical states of matter.

C2H4(g) + H2(g) = C2H6 (g)
Write the expression for the equilibrium constant for this equilibrium.

K=