Difference between adiabatic process and isothermal process.?

An isothermal process is that process that takes place at constant temparature. An adiabatic process is that process that takes place in a system without the system loosing or gaining energy(usually heat) from the outside. Take an example of a closed cylinder with a piston on top. should you lower the piston, the air inside the cylinder gets compressed, the molecules move faster and the temparature within rises i.e. the temparature of the system has increased without getting energy from outside Should you pull the piston up, the air inside the cylinder expands and the temparature inside decreases, without actually losing heat to the outside. So you see that in an adiabatic system, the temparature can change withuot actually getting heat from outside the system or by losing heat to it Thats what is meant by an adiabatic system. While for temparature of a process to be maintained (i.e. for a process to be isothermal), either heat has to be released to the outside, or be gained from it.

In thermodynamics, an adiabatic process or an isocaloric process is a process in which no heat is transferred to or from working fluid. The term "adiabatic" literally means an absence of heat transfer; for example, an adiabatic boundary is a boundary that is impermeable to heat transfer and the system is said to be adiabatically (or thermally) insulated. An insulated wall approximates an adiabatic boundary. Another example is the adiabatic flame temperature, which is the temperature that would be achieved by a flame in the absence of heat loss to the surroundings. An adiabatic process which is also reversible is called an isentropic process. The opposite extreme, in which the maximum heat transfer with its surroundings occurs, causing the temperature to remain constant, is known as an isothermal process. Since temperature is thermodynamically conjugate to entropy, the isothermal process is conjugate to the adiabatic process for reversible transformations. A transformation of a thermodynamic system can be considered adiabatic when it is quick enough so that no significant heat transfer happens between the system and the outside. The adiabatic process can also be called quasi-static. At the opposite, a transformation of a thermodynamic system can be considered isothermal if it is slow enough so that the system's temperature can be maintained by heat exchange with the outside.

In isothermal process the temperature of the system is maintained constant. But it is not in the case of adiabatic. Simple