$A$ measure of the degree of disorder of a system is known as

During phase change,entropy

Find the change in the entropy in the following process: $100 \, g$ of ice at $0^{\circ}C$ melts when dropped in a bucket of water at $50^{\circ}C$. (Assume the temperature of the water does not change). The result is in $cal/K$.

An ideal gas in a cylinder is separated by a piston in such a way that the entropy of one part is $S_{1}$ and that of the other part is $S_{2}$. Given that $S_{1} > S_{2}$. If the piston is removed,then the total entropy of the system will be:

Can the whole of heat be converted into work?

Write an example in which the first law of thermodynamics is allowed but is never observed.