where the constant is characteristic of the process, and 
the ratio of specific heats of the gas 
is approximately constant for the gas. [P7.4]
for: a fixed quantity of ideal gas
states: that where the constant is characteristic of the process, and the ratio of specific heats of the gas is approximately constant for the gas. [P7.4]
characterizes: an adiabatic process. [P7.4]
Copyright 1997, The Open University