PV = nRT

Definition

PV = nRT is the ideal gas law, which describes the relationship between the pressure (P), volume (V), amount of substance (n), and absolute temperature (T) of an ideal gas. This fundamental equation is used to predict the behavior of gases and understand various gas-related phenomena.

5 Must Know Facts For Your Next Test

1. The ideal gas law is used to relate the pressure, volume, amount of substance, and absolute temperature of a gas, allowing for the prediction of the behavior of gases in various situations.
2. The constant 'R' in the equation is the universal gas constant, which has a value of approximately 0.082057 L⋅atm⋅mol^-1⋅K^-1.
3. The ideal gas law assumes that gas molecules are point-like particles with no volume and no interactions between them, which is an idealized model of real gases.
4. The ideal gas law is particularly useful in the study of chemical reactions involving gases, as it allows for the calculation of the volume, pressure, or amount of a gas produced or consumed.
5. The ideal gas law is a fundamental concept in the study of thermodynamics and is essential for understanding the behavior of gases in various applications, such as in the design of engines, refrigeration systems, and chemical processes.

Review Questions

• Explain how the ideal gas law (PV = nRT) can be used to determine the volume of a gas produced or consumed in a chemical reaction.
  • The ideal gas law can be used to determine the volume of a gas produced or consumed in a chemical reaction by rearranging the equation to solve for the volume (V). If the pressure (P), amount of substance (n), and temperature (T) are known, the volume can be calculated using the formula V = (nRT)/P. This allows for the prediction of the volume of a gas that will be produced or consumed based on the stoichiometry of the reaction and the conditions of the system, which is crucial in the study of gaseous reactions and processes.
• Describe how the ideal gas law can be used to understand the relationship between the pressure and volume of a gas as the temperature changes, and explain the significance of this relationship.
  • The ideal gas law can be used to understand the inverse relationship between the pressure and volume of a gas as the temperature changes. Specifically, if the temperature of a gas increases while the amount of substance and pressure remain constant, the volume of the gas will increase proportionally. Conversely, if the temperature decreases, the volume will decrease. This relationship is known as Boyle's law and Charles' law, and it is fundamental to understanding the behavior of gases in various applications, such as the operation of internal combustion engines, the design of gas storage and delivery systems, and the analysis of chemical reactions involving gases.
• Analyze how the ideal gas law can be used to determine the molar mass of an unknown gas by measuring its pressure, volume, temperature, and mass, and explain the significance of this application.
  • The ideal gas law can be used to determine the molar mass of an unknown gas by measuring its pressure (P), volume (V), temperature (T), and mass (m). By rearranging the ideal gas law to solve for the amount of substance (n), and then dividing the mass (m) by the amount of substance (n), the molar mass can be calculated using the formula: molar mass = m/n. This application of the ideal gas law is significant because it allows for the identification and characterization of unknown gases, which is crucial in various scientific and industrial applications, such as in the analysis of gas mixtures, the detection of air pollutants, and the development of new materials and chemical processes.

Related terms

Ideal Gas: An ideal gas is a hypothetical gas that follows the ideal gas law precisely, with no intermolecular interactions and perfectly elastic collisions between particles.

Moles: The mole (symbol: mol) is the SI unit for the amount of a substance, and it is used to measure the number of particles (atoms, molecules, or ions) in a sample.

Absolute Temperature: Absolute temperature is measured on the Kelvin scale, where 0 K represents the lowest possible temperature (absolute zero) and temperatures are expressed in units of Kelvin (K).