Ideal gas constant

Definition

The ideal gas constant (R) is a proportionality factor in the ideal gas law equation, $PV = nRT$, which relates the pressure, volume, amount of gas, and temperature. Its value depends on the units used for these variables.

5 Must Know Facts For Your Next Test

1. The ideal gas constant R has different values depending on the units used: 8.314 J/(mol·K), 0.0821 L·atm/(mol·K), and 62.36 L·mmHg/(mol·K).
2. It is derived from the combination of Boltzmann's constant and Avogadro's number.
3. The ideal gas law assumes that gases behave ideally, meaning they follow certain assumptions like no interaction between molecules and negligible molecular volume.
4. In real-world applications, gases deviate from ideal behavior at high pressures and low temperatures.
5. The value of R can be experimentally determined using conditions where gases closely approximate ideal behavior.

Review Questions

Related terms

Ideal Gas Law:

An equation of state for an ideal gas, given by $PV = nRT$.

Boltzmann's Constant: A physical constant relating the average kinetic energy of particles in a gas with the temperature, approximately equal to $1.38 \times 10^{-23}$ J/K.

Avogadro's Number:

The number of constituent particles (usually atoms or molecules) in one mole of a substance, approximately $6.022 \times 10^{23}$ mol^{-1}.