Which of the following describes the reaction relationship expressed through the equation PV=nRT?

• A. The relationship between pressure and volume
• B. The relationship between concentration and temperature
• C. The relationship between moles of gas and supporting interactions
• D. The relationship among pressure, volume, and amount of gas at constant temperature

Answer: (D)

The equation PV=nRT is the ideal gas law, which describes the behavior of an ideal gas in terms of its pressure (P), volume (V), temperature (T), and the number of moles of gas (n) present. This equation illustrates how these variables are interrelated.

When examining the ideal gas law, one can identify that under a fixed temperature (as indicated by the constant nature of R, the ideal gas constant), the pressure and volume of a gas are inversely related. If the temperature is held constant, an increase in volume will result in a decrease in pressure, and vice versa. Additionally, the amount of gas—in moles (n)—also influences these relationships. Thus, the equation shows how pressure, volume, and the amount of gas interact when the temperature remains unchanged.

This relationship allows for the prediction of how gas behavior changes with varying one or more of these factors while keeping the others constant. Therefore, the best characterization of the relationships outlined by the ideal gas law is that it describes how, at constant temperature, the pressure, volume, and amount of gas are all interconnected.