(1) For an adiabatic free expansion of an ideal gas, the gas is kept in an insulated container and then permitted to enlarge in a vacuum. Since there is no external pressure for the gas to enlarge against, the work done by or on the system is zero. Since this process does not involve any exchange of heat transfer or work, heat will not escape and temperature of system will rise. For diathermic container, heat will escape the container and hence temperature of container will remain same