Question

Which of these is a soft heavy metal melts at ${30}^{0}C$ and used in making heat sensitive thermometer?

• A. Galium
• B. Sodium
• C. Potassium
• D. Caesium

Answer 1

The correct option is A Galium

Gallium is a silvery, glass-like, soft metal. Its properties are close to the non-metals in the periodic table and its metallic properties are not as metallic as most other metals. Solid gallium is brittle and is a poorer electrical conductor than lead. Gallium has the second largest liquid range of any element and is one of the few metals that is liquid near room temperature (m.pt. 29.76), melting in the hand. So it is used in thermometer.

Hence option $A$ is correct.