In the manufacturing of bricks, the presence of excess Alumina (Al2O3) causes
- AThe brick to become brittle and weak.
- BThe brick to crack and warp during drying.Correct
- CImprovement in the impermeability of the brick.
- DThe brick to melt and lose its shape during burning.
Solution
Concept
Effects of Excess Alumina in Bricks
Formula
N/A
Step-by-step solution
1. Review the question about the effects of excess alumina in brick manufacturing. 2. Recall that excess alumina causes raw bricks to absorb extra water, leading to shrinkage, cracking, and warping during drying. 3. Select Option (b) as the correct choice.
Explanation
When present in excess, alumina causes raw bricks to absorb too much water, leading to severe shrinkage, cracking, and warping as the bricks dry and burn.
Shortcut
To remember the effect of excess Alumina in bricks, use the mnemonic "Alumina = Absorbs & Alters": - Absorbs Water: Excess alumina absorbs too much water, making the raw clay overly plastic. - Alters Shape: Excessive shrinkage during drying causes the brick to crack and warp.
Common mistake
A common mistake is selecting option D by confusing the effect of excess alumina with that of excess lime or alkalies, which cause bricks to melt and lose shape during burning. Another frequent mistake is choosing option A, confusing excess alumina with excess silica, which makes bricks brittle and weak.
Correct answer: B) The brick to crack and warp during drying.