A sample of ideal gas undergoes three independent changes described below. For each change, identify the type of thermodynamic process (isothermal, adiabatic, or cyclic) and give a clear justification based on the First Law of Thermodynamics and the properties of an ideal gas.
(i) One mole of the gas, enclosed in a thin-walled glass bulb, is very slowly compressed while the bulb is kept completely immersed in a large water bath maintained at a constant temperature of 25∘C. The pressure of the gas increases from 1.0×105Pa to 1.5×105Pa.
(ii) The same gas is allowed to expand in a highly polished, perfectly insulated steel vessel fitted with a frictionless piston. The volume doubles in a very short time.
(iii) Starting from its initial state, the gas is taken through a sequence of changes that finally brings it back to its original pressure, volume and temperature. In the entire sequence the net work done by the gas is 1200J and the net heat supplied to it is 1200J. State the nature of this overall process.