Question

How cold is absolute zero?

Answer 1

The lowest possible temperature where nothing else could be colder than this and no heat energy remains in a substance is defined as absolute temperature. It is the point at which the particles will have a minimal vibrational motion. It is the point where a thermodynamic system will have minimum energy. Absolute zero can also be known as the zero kelvin because it is zero on the Kelvin scale.

Complete step by step solution:
The temperature of absolute zero is equal to $- 273^\circ C$ or $459.67^\circ F$. According to the law of physics, this is the lowest temperature that could possibly be achieved. To answer the question of how cold is the absolute zero is that it is the coldest that any entity could possibly be.
This concept of absolute zero as a limiting temperature has various other consequences. For example, all the motions of the molecule will not cease at absolute zero. But there will be no energy that will be available from the motion of the molecule for the transfer to other systems. Therefore we can say that the energy will be minimal at absolute zero.

Additional Information:
The velocity at which molecules vibrate will determine the temperature of an object. However, even in absolute zero the molecules inside the object will never stop vibrating. They will still oscillate at the slowest speed. And that is why achieving absolute zero is not completely possible. But scientists have approached this level.

Note:
Note that however the absolute temperature is the lowest possible temperature but they are never the lowest enthalpy state possible. This is because all the real substances when they are cooled begin to make off from the ideal gas behavior and they approach the change of state. Firstly they will change to liquid and then to solid.