What is the ideal gas law used for?
You can use one of two formulation of the ideal gas law according with what you want know.
where P = absolute pressure
n = number of mol = mass (in gramms)/ molecular Mass
R is the universal costant of ideal gas = 0.082 L x Atm /(mol K) or 8,31 J /(mol K)
T = absolute temperature in K
This is usefull if you want find a parameter andyou know all the others
the second formulation is
it allows to see the change of a parameter (P, V or T) if you know the others