1. The problem is to understand and use the ideal gas law formula: $$PV = nRT$$ where $P$ is pressure, $V$ is volume, $n$ is the number of moles, $R$ is the ideal gas constant, and $T$ is temperature in Kelvin. 2. This formula relates the pressure, volume, and temperature of an ideal gas with the amount of gas present. 3. Important rules: - $P$ and $V$ must be in consistent units (e.g., atm and liters). - $T$ must be in Kelvin. - $R$ is a constant, commonly $0.0821$ when $P$ is in atm and $V$ in liters. 4. To solve for any variable, rearrange the formula. For example, to find $n$: $$n = \frac{PV}{RT}$$ 5. If you need to solve for $T$: $$T = \frac{PV}{nR}$$ 6. If you need to solve for $P$: $$P = \frac{nRT}{V}$$ 7. Always check units and convert temperature to Kelvin by adding 273.15 if given in Celsius. This formula is fundamental in chemistry and physics for gas behavior calculations.