Changes

The '''ideal gas law''', is an [[equation of state]] for an ideal gas. It combines three [[gas]] laws ([[Dalton's Law of Partial Pressures|Dalton's Law]], [[Boyle's Law]] and [[Charles' Law]]) into one equation:  

The '''ideal gas law''', is an [[equation of state]] for an ideal gas. It combines three [[gas]] laws ([[Dalton's Law of Partial Pressures|Dalton's Law]], [[Boyle's Law]] and [[Charles' Law]]) into one equation:  

:PV = nRT

:<math>PV = nRT</math>

where

where

   

   

*P is the [[pressure]] of gas;   

*''P'' is the [[pressure]] of gas;   

*V the [[volume]] the gas occupies;  

*''V'' the [[volume]] the gas occupies;  

*T the absolute [[temperature]] (meaning it must be in [[Kelvin]] or [[Rankine]]);  

*''T'' the absolute [[temperature]] (meaning it must be in [[Kelvin]] or [[Rankine]]);  

*n is the number of [[Mole (chemistry)|moles]] of the gas occupying the volume V;  

*''n'' is the number of [[Mole (chemistry)|moles]] of the gas occupying the volume V;  

*R is the [[gas constant]].

*''R'' is the [[gas constant]].

The gas constant can be expressed in any number of units, but the most common representations are <math>0.0821\,L \cdot atm \cdot mole^{-1} \cdot K^{-1}</math> or <math>8.314\,J \cdot mole^{-1} \cdot K^{-1}</math>

The gas constant can be expressed in any number of units, but the most common representations are <math>0.0821\,L \cdot atm \cdot mole^{-1} \cdot K^{-1}</math> or <math>8.314\,J \cdot mole^{-1} \cdot K^{-1}</math>

Since this is just a model, real gases only obey the ideal gas law approximately, not perfectly. Generally, the ideal gas assumption is accurate for unreactive gases at high temperature and/or low pressure. A good rule of thumb is that the assumption can be used above room temperature and below 1 [[atmosphere]] of pressure.

Since this is just a model, real gases only obey the ideal gas law approximately, not perfectly. Generally, the ideal gas assumption is accurate for unreactive gases at high temperature and/or low pressure. A good rule of thumb is that the assumption can be used above room temperature and below 1 [[atmosphere]] of pressure.

==density==

==Density==

With the molar mass (M), the ideal gas law can be used to calculate the [[density]] of a gas, d.

With the molar mass (''MÄÄ), the ideal gas law can be used to calculate the [[density]] of a gas, ''d''.

PM=dRT

:<math>PM=dRT</math>

[[category:physics]]

[[category:physics]]

[[category:Chemistry Laws and Principles]]

[[category:Chemistry Laws and Principles]]