You can get the concept of: The coefficient of thermal expansion, general equation of state of ideal gases, universal gas constant, Gay-Lussac Law.
Principle: State of the gas determined by its temperature, pressure and quantity of the substance. For the case of an ideal gas, these state variables are related by the general equation. For the special case of the gas under isobaric conditions this equation is called the first law of Gay-Lyusakka. In the experiment, checking the conformity of theoretical and experimental data, the example of air.
