Final answer:
The pressure will increase when more gas molecules are added to a container without changing its volume. The increase in collisions of gas particles with the container walls results in higher pressure. Equilibrium positions can also shift with changes in pressure or temperature. Option 2 is correct.
Step-by-step explanation:
If the number of gas molecules increases, the pressure will increase. This is because each time gas particles strike the walls of their container, they exert force on the walls. More gas particles mean more collisions and consequently a greater force applied to the container walls. Given that the walls of the container have a constant area, this results in increased pressure.
Additionally, under certain conditions, changing the amount of energy in a system can affect the volume and pressure of a gas. For instance, adding a significant amount of energy can increase the gas's volume and pressure, or extracting a large amount of energy can decrease the gas's volume and pressure.
Moreover, the equilibrium constant for a reaction involving gases, such as 2SO2(g) + O2(g) = 2SO3(g), may change with temperature. An increase in pressure due to more gas molecules is analogous to an increase in gaseous reactants, shifting the equilibrium toward fewer moles of gaseous products.