The ideal gas law is an important relationship that describes the state of an ideal gas.
An ideal gas is a theoretical gas where we neglect both molecular size and inter molecular attractions, this is of course not exactly how things happen at a microscopic level but it makes a realistic approximation for many different gases which allows for easier calculations.
P is the pressure of the gas, V its volume and T its temperature. Three important variables that define the state of a given gas.
R is a constant called the ideal gas constant, 8.314 J/(K.mol) and n is the amount of substance of gas in moles.
This approximation works best for monoatomic gases at low pressures where the fact that we neglect the molecular size is the most realistic and since different molecules have a large space to roam, the interactions between them can be neglected.
Do you know the more general formula, for real gases ?
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