For an ideal gas, classify the following pairs of properties as directly or inversely proportional. P and n, V and n, P and T, T and V, P and V.

**Answer:**

P and n are directly proportional

V and n are directly proportional

P and T are directly proportional

T and V are directly proportional

P and V are inversely proportional

The ideal gas equation is a mathematical description of the thermodynamic properties of gases, such as pressure (P), volume (V), a number of moles (n), ideal gas constant (R), and temperature (T). At low pressures and high temperatures, some gases behave like ideal gases. This gas type is characterized by the ideal gas equation.