Question

# In crystals, the state of complete order and of lowest energy is formed at 0$^\circ$C.a.) – Trueb.) – False

Hint: The given statement relates to one of the laws of thermodynamics. It is relatable to the entropy of the system, or a crystal. So, we will define the laws, and the statement can be identified whether it is correct or wrong.

Complete step by step solution:
Now, first we will talk about the first law of thermodynamics. It is defined in consideration with the law of conservation of energy.
So, we can say the given statement is not related to the first law of thermodynamics, as the first law isn't in relation with the order of the crystal.
Talking about the second law of thermodynamics; it can be defined on the basis of work done in consideration with the pressure, temperature, and volume.
We can also define the reversibility, and irreversibility of the heat exchange, or we can say the work done in the process.
Thus, the second law is not considerable.
Now, we have the third law of thermodynamics, it states that the perfect crystalline at a value equal to zero at absolute zero for the factor i.e. entropy.
We can say that in the other terms entropy will be zero when the temperature will move towards 0 K.
Now, we can say in the crystals, the state of complete order, and of lowest energy is formed at the 0 K.
In the last, we concluded that the given statement is false due to the value of temperature, i.e. 0$^\circ$C.

Hence, the answer is (B).

Note: Don’t get confused while reading the statement, as in the question we are talking about the order, and energy of the crystal at the given temperature. So, it is only relatable in terms of the laws of thermodynamics.It should also be noted that, other than 0 K, there will definitely be some kind of thermal motion within the crystal.