Isothermal process

An isothermal process is a thermodynamic process, in which the temperature remains constant: ΔT = 0.The heat transfer into or out of the system typically must happen at such a slow rate that the thermal equilibrium is maintained. This typically occurs when a system is in contact with an outside thermal reservoir (heat bath), and the change occurs slowly enough to allow the system to continually adjust to the temperature of the reservoir through heat exchange. in an isothermal process, the value ΔT = 0 and therefore ΔU = 0 (only for an ideal gas) but Q ≠ 0.