Name the international organization that approves the names of elements. Give an example with an explanation to show that the Law of Conservation of Mass applies to physical changes as well.

(N/A) The international organization that approves the names of elements is the International Union of Pure and Applied Chemistry $(IUPAC)$.
$(b)$ The melting of ice into water is a physical change. To demonstrate the Law of Conservation of Mass,take a piece of ice in a small flask,cork it,and weigh it (let this be $W_{\text{ice}} \text{ g}$). Heat the flask gently so that the ice (solid) melts into water (liquid). Weigh the flask again (let this be $W_{\text{water}} \text{ g}$). It is observed that there is no change in the total mass of the system.
i.e.,$W_{\text{ice}} = W_{\text{water}}$
$\text{Ice (solid)} \xrightarrow{\text{Heat}} \text{Water (liquid)}$
This process represents a physical change. Since the mass remains constant before and after the change,it proves that the Law of Conservation of Mass holds true for physical changes.