Question

Froth flotation is primarily based on differences in:

• A. Particle size
• B. Electrical conductivity
• C. Surface wettability
• D. Density of particles

Hint:

Logic Tip: "Wettability" just means how much a material "likes" water. If it hates water (hydrophobic), it will grab onto an air bubble to float away. Flotation = Floating on bubbles = Surface Wettability.

Answer 1

The Correct Option is C

Concept:
Froth flotation is a highly versatile method for physically separating particles based on differences in the ability of air bubbles to selectively adhere to specific mineral surfaces in a water/slurry mixture.

Step 1: In mining, valuable minerals are often mixed with worthless rock (gangue). They need to be separated without dissolving them.

Step 2: Chemicals called "collectors" are added to the slurry. These chemicals selectively bind to the valuable mineral particles, making their surfaces hydrophobic (water-repelling).

Step 3: Air is agitated into the slurry tank to create bubbles.

Step 4: Because the valuable minerals are now hydrophobic (low wettability), they attach to the air bubbles to escape the water. The bubbles float them to the surface as a froth.

Step 5: The gangue remains hydrophilic (high wettability), stays completely wetted by the water, and sinks. Thus, the separation is driven entirely by surface wettability.