The ideal gas law is PV = nRT. Explain what each variable is in this equation and include a common unit used to measure that variable Variable P V n R T Property Pressure Unit Pa/bar/atmosphere L/cm3 mol atm*L/mol* K K

1 answer

The ideal gas law is represented by the equation \( PV = nRT \), where each variable corresponds to a specific property of a gas. Here's a breakdown of each variable along with common units used to measure them:

  • P (Pressure): This is the force exerted by gas particles per unit area. Common units for pressure include:

    • Pascals (Pa)
    • Bar (bar)
    • Atmospheres (atm)
  • V (Volume): This is the space occupied by the gas. Common units for volume include:

    • Liters (L)
    • Cubic centimeters (cm³)
  • n (Number of moles): This represents the amount of substance of the gas measured in moles (mol). There are no common alternative units for this variable in the context of the ideal gas law.

  • R (Ideal gas constant): This is a proportionality constant that relates the other variables in the ideal gas law. Its value depends on the units used for pressure, volume, and temperature. Common values of \( R \) include:

    • \( 8.314 , \text{J/(mol·K)} \) (when pressure is in Pa and volume is in m³)
    • \( 0.0821 , \text{L·atm/(mol·K)} \) (when pressure is in atm and volume is in L)
  • T (Temperature): This is the measure of the average kinetic energy of gas particles, and it must be measured on an absolute scale (Kelvin). The common unit is:

    • Kelvin (K)

In summary, the ideal gas law is a relationship used in physics and chemistry to describe the behavior of ideal gases, where pressure, volume, number of moles, the ideal gas constant, and temperature are interconnected.