Problem 5i.11- using molarity in place of pressure?

[claudia_1h]

So this problem basically asks you to calculate the reaction quotient given the amount of each substance in a container and the volume of that container. All of these substances are gases however, so don't we need to use partial pressures, not molar concentrations? The answer key just divides each number of moles by volume for each term... why is this acceptable?

[Jiyoon_Hwang_2I]

I think you use the concentrations instead of the partial pressures because the given value of K is Kc and they are asking you for Qc so you should keep it consistent by using concentrations instead of partial pressures.

[Skyllar Kuppinger 1F]

You can also use concentration for gases. This is called Kc (k with a subscript of c). So just make you write Kc= (insert answer) instead of just K= (insert answer)

[Shail Avasthi 2C]

You can either use partial pressure or concentration when calculating equilibrium for gasses.