For the reaction H2(g)+I2(g)⇌2HI(g), Kc = 55.3 at 700 K. In a 2.00-L flask containing an equilibrium mixture of the three gases, there are 0.051g H2 and 4.39g I2. What is the mass of HI in the flask?

Question

anonymous · Answer

First set up the equilibrium expression. Solve to find the equilibrium concentration of HI.
Then find the number of moles of HI.
Convert moles to mass.

anonymous · Answer

I did, but I ended up with 40 grams, which is way too high.

jfraser · Answer

@disguy2 did you convert the masses of $H_2$ and $I_2$ into moles first?