Values of Gas Constant in ideal gas law can vary depending on the units used, this short article discuss what is the ideal gas law and provides some common values used for the ideal gas law equation.

## What is the Ideal Gas Law?

The Ideal Gas Law States that,

**PV= nRT**

*P*= Pressure of Gas*V*= Volume of n moles of gas *n*= number of moles of gas,* which is also defined as weight/molecular weight**R*= Gas Constant *T*= Temperature

This equation only works when all the gases are behaving themselves in other word ideal gas state. There is a relationship between Pressure, Volume and Temperature when using this equation. This equation also allows us to approximate the behaviour of gases. Using this ideal gas we can also determine the weight of a gas if the volume is known and vice-versa.

Parameters | English | Metric | S.I |

Pressure | 1 atm | 1.033 kg_{f}^{3}/cm^{2} | 1.01325 bar |

Gas Constant | 0.73 atm ft^{3}/lb mole^{ o}R | 0.085 kg_{f} m^{3}/k mole K | 0.083 Bar m^{3}/k mole K |

Molar Volume | 359 ft^{3}/lb mole | 22.414 m^{3}/k mole | 22.414 m^{3}/k mole |

Temperature | 492 ^{o}R | 273 K | 273 K |

## Gas Constant

Gas constant **R** is universal, a dimensional quantity.

**R** values depend on the Units involved. The table below summarizes the values used for the gas constant at different measurement units in relation to the ideal gas law.

Temperature | Pressure | Volume | Gas Constant ‘R’ | Units of Gas Constant |

R | psia | in^{3} | 18.51 | in^{3} psia/lb mole R |

R | psia | ft^{3} | 10.73 | ft^{3} psia/lb mole R |

R | atmospheres | ft^{3} | 0.73 | ft^{3} atm/lb mole R |

R | lbf/ft^{2} | ft3 | 1545.35 | ft lbf/lb mole R |

K | Pa | m^{3} | 8314 | m^{3} Pa/k mole K |

K | atmospheres | m^{3} | 0.08206 | m^{3} atm/k mole K |

K | atmospheres | cm^{3} | 82.06 | cm^{3} atm/g mole K |

K | cm Hg | cm^{3} | 6239.79 | (cm^{3} cm Hg) g mole K |

K | kPa | m^{3} | 8.314 | kJ/kg mole K |

K | Pa | m^{3} | 8314.47 | J/kg mole K |

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