
Which one of the following pairs of metals constitutes the lightest metal and the heaviest metal, respectively?
- Lithium and mercury
- Lithium and osmium
- Aluminium and osmium
- Aluminium and mercury
Explanation
Option (b) is correct
- Lithium is the lightest metal and the least dense solid element. It has a density of approximately 0.534 g/cm³, about half that of water. Osmium is the heaviest metal (densest naturally occurring element). It has a density of approximately 22.59 g/cm³, making it twice as dense as lead.


