Question

Name the ore of mercury and state the form in which it is found in nature. Write the chemical equations along with the condition required for the reactions involved in the extraction of mercury from its ore.

Answer 1

Step 1: Name the ore of mercury:
The chief ore of mercury is Cinnabar.
- Chemical formula: HgS (mercury(II) sulfide)

Step 2: Natural form of mercury:
- In nature, mercury is found in the form of its sulfide ore (HgS), commonly known as cinnabar.
- It is a bright red mineral.

Step 3: Extraction of mercury – Steps and reactions:
The extraction of mercury from cinnabar involves two main steps:

Step 3.1: Roasting of cinnabar in air:
Cinnabar is heated in the presence of oxygen (air), where it gets oxidized to form mercury and sulfur dioxide:
\[ 2HgS + 3O_2 \xrightarrow{\text{Heat}} 2Hg + 2SO_2 \]
- This reaction is carried out in a furnace.
- Mercury vapors formed are condensed to get liquid mercury.

Step 3.2: Purification:
- The mercury obtained is purified by condensation and collection.

Step 4: Conclusion:
- The ore of mercury is Cinnabar (HgS).
- It is found as mercury(II) sulfide in nature.
- The extraction involves roasting HgS in air to get mercury metal and SO₂ gas.