state and explain how the concentration of nitrogen gas would be affected by an increase in pressure

Depends upon the reaction doesn't it? What's the reaction?

the reaction is:

2NO yield N2 + O2

An increase in pressure will not affect the equilibrium. Pressure shifts the equilibrium to the side with the few mols. In this case both sides have 2 mols gas; therefore, the reaction will be unchanged.

The concentration of nitrogen gas would not be affected by an increase in pressure alone. Concentration refers to the amount of a substance per unit of volume. It is defined as the ratio of the number of moles of a solute to the volume of the solution.

However, an increase in pressure can affect the overall number of gas molecules present in a given volume. According to the ideal gas law, PV = nRT, where P represents pressure, V represents volume, n represents the number of moles, R is the ideal gas constant, and T represents temperature. By rearranging the equation, we can see that an increase in pressure can result in an increase in the number of moles (n), assuming temperature and volume remain constant.

In a closed system, if the pressure increases, the system may experience compression, which can lead to a decrease in volume. However, if the volume remains constant, and the number of moles increases as a result of increased pressure, then the concentration of nitrogen gas can be said to increase.

It is noteworthy to mention that in order to have a concentration change, the system must be confined, and there should be no escape or addition of nitrogen gas to the system. Concentration is dependent on the number of moles and volume, not pressure alone.