What does "n" represent in the ideal gas equation pV = nRT?

In the ideal gas equation ( pV = nRT ), "n" represents the number of moles of the gas. This equation describes the relationship between pressure (p), volume (V), temperature (T), and the amount of substance (in moles) of an ideal gas.

Understanding the role of "n" is crucial because it allows us to quantify how much gas is involved in a reaction or a system. The equation implies that when the number of moles increases, keeping pressure and temperature constant, the volume the gas occupies will also increase.

This concept is fundamental in thermodynamics and physical chemistry, as it connects the macroscopic properties of gases to the microscopic number of molecules present. Other quantities in the equation—pressure, volume, and temperature—while crucial for gas behavior, do not encompass the representation of the quantity of gas itself, which is specifically indicated by "n". This understanding is essential for calculations involving stoichiometry, gas laws, and thermodynamics in general.