Which one of the following elements will remain as liquid inside pure boiling water ?

To determine which element remains liquid in pure boiling water, we must reference the boiling points of various elements. The key is to find an element whose boiling point is higher than 100°C (the boiling point of water at standard atmospheric pressure).

1. Element and Boiling Points:

   • Mercury (Hg): Boiling point = 356.73°C
   • Gallium (Ga): Boiling point = 2204°C
   • Bismuth (Bi): Boiling point = 1564°C
   • Bromine (Br): Boiling point = 58.8°C

2. Analysis of Boiling Points:

   • Elements like mercury, gallium, and bismuth have boiling points significantly higher than 100°C, meaning they will remain liquid when water boils.
   • Conversely, bromine has a boiling point of 58.8°C, which is below that of water, indicating it would vaporize before water boils.

3. Conclusion: The element that remains liquid in pure boiling water is mercury (Hg), as well as gallium (Ga) and bismuth (Bi), due to their higher boiling points. However, among common elements encountered, mercury is often specifically noted for being liquid at room temperature and also remains liquid in boiling water.

In summary, mercury is the best example of an element that remains in the liquid state while in the vicinity of boiling water.