The ideal gas law of physics and chemistry says that PV = nRT. This law is a statement of the relationship between four variables (P, V, n, and T) that reflect properties of a quantity of gas in a container. The law enables us to make accurate predic
tions of the value of any one of the four variables from the values of the other three. The symbol R (called the molar gas constant) is the sole parameter or constant of the law. R stands for a fixed number that has been shown through experiments to equal approximately 8.314472. Eight methods are available to analyze the data from a relevant experiment to determine the value of R. These methods are specific instances of eight general methods that scientists use to determine the value(s) of the parameter(s) of a model equation of a relationship between variables. Parameter estimation is one step in the study of a relationship between variables.
