2- Addition of an appropriate catalyst will result in a greater amount of C(g)
3- Lowering the reaction temperature to 100 Celsius will result in the formation of a greater amount of C(g)
4- Addition of an inert gas at constant volume will have little or no effect on equilibrium.
Please refer to the attached file.
A(g) + B(g) + ΔH ↔ 2 C(g)
Because as the volume is increased twice as much, pressure of all A, B, and C decrease by half.
Now, divide [A], [B], and [C] by two, you get
This solution is provided in 161 words in an attached .doc file. It describes how volume and pressure are affected in an endothermic reaction. It also discusses Le Chatelier Principle and how enthalpy and equilibrium change with temperature.