Bricks MCQ with answer and solution

Concept

Sand (silica) in brick earth prevents cracking, shrinkage and warping of raw bricks.

Step-by-step solution

1. Brick earth has alumina, silica (sand), lime, iron oxide and magnesia. 2. Alumina gives plasticity but causes cracking, shrinkage and warping when it is too much. 3. Sand (silica) is added to reduce this. 4. Sand mainly prevents cracking, shrinkage and warping of raw bricks. 5. In the options, the standard textbook answer is cracking.

Explanation

Sand is the silica in brick earth. It makes a uniform structure and stops raw bricks from cracking while drying and burning. It also helps reduce shrinkage and warping, but the usual textbook answer is cracking.

Why the other options are wrong

Cracking and shrinkage are also prevented.

Shortcut

Sand = silica = prevents cracking, shrinkage and warping of raw bricks.

Common mistake

Choosing shrinkage or warping, as sand helps with these too. Many books list cracking first.