At the absolute zero temperature, the entropy of any thermodynamic system is ___.

At the absolute zero temperature, the entropy of any thermodynamic system is ___.

a. One
b. More that one
c. Zero
d. None of the above

Correct Answer : c. Zero

Explanation :

Consider a solid at very low temperature. The molecules in solid are arranged in a regular pattern called lattice. This lattice has periodic structure. The basic molecular arrangement, called as unit cell, is repeated through solid in periodic structure of lattice. At nonzero temperature, the thermal activity within the solid produces a motion molecules about their preference position in the lattice. They behave like simple harmonic oscillators, vibrating about their corresponding equilibrium positions. As T decreases towards absolute zero, the kinetic energy of molecules also decreases and becomes zero at absolute zero temperature. Thus the entropy also becomes zero.