Question

A spoon made of metal X melts when it is used to stir hot water. Identify the metal X.

• A. Germanium
• B. Lithium
• C. Strontium
• D. Caesium

Answer 1

The correct option is D Caesium

Caesium is a soft metal and has a melting point of ${28}^{\circ }C$. It is generally in liquid state at or near room temperature. So if you use a caesium spoon, it would start melting the moment you use it to stir hot water, because the temperature of hot water will be more than ${55}^{\circ }C$. So it is practically impossible to stir hot water with a caesium spoon. If you look at the other metals in the option, you will see that lithium has a melting point of ${180}^{\circ }C$ , Strontium melts at ${768}^{\circ }C$ and Germanium at ${938}^{\circ }C$ , which is much more than that ${100}^{\circ }C$ (water starts turning into steam at this temperature) so stirring hot water is possible with these metal spoons.