Question

Which of the following metals possesses the highest melting point?

• A. Sodium (Na)
• B. Lithium (Li)
• C. Potassium (K)
• D. Cesium (Cs)

Hint:

Melting points generally decrease down a group for alkali metals, because there is greater electron shielding, and weaker metallic bonding. There are no strong or weak covalent bonds between metals, instead, the metal atoms share a “sea of electrons”, so metals with strong metallic bonds have high melting points.

Answer 1

The Correct Option is B

Among the alkali metals, lithium has the highest melting point due to its small atomic size and strong metallic bonding. The melting point trend in Group 1 elements decreases as atomic size increases, weakening the metallic bonds. Therefore, the order of melting points is:
• Lithium (Li): Highest melting point
• Sodium (Na)
• Potassium (K)
• Cesium (Cs): Lowest melting point
This trend highlights the relationship between atomic size and bond strength in metallic structures.