Building Materials
Excess of alumina in brick earth makes the brick

To lose cohesion
Brittle and weak
Impermeable
To crack and warp on drying

ANSWER DOWNLOAD EXAMIANS APP

Building Materials
When a brick is immersed in water for 24 hours and then dried, if

All listed here
50 percent surface is covered with grey or white deposits, the brick has serious efflorescence
No grey or white deposits appear on the surface, the brick is free from soluble salts
10 percent surface is covered with grey or white deposits, the brick has slight efflorescence

ANSWER DOWNLOAD EXAMIANS APP