Civil Engineering MCQAE Level Civil Engineering
Efflorescence in bricks is caused by:
Building MaterialsBricksEASY
Choose the correct answer
A
Excess water during manufacture
B
Presence of soluble salts (Na₂SO₄, MgSO₄) in brick that leach to surface on drying, leaving white patches
C
Overburning
D
Low temperature firing
Correct Answer
B. Presence of soluble salts (Na₂SO₄, MgSO₄) in brick that leach to surface on drying, leaving white patches
Why is this the answer?
Efflorescence: water carries soluble salts to brick surface → white deposits on drying. IS 1077 rates: nil/slight/moderate/heavy/serious. Avoided by using low-salt raw materials; treated by dilute HCl wash.
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This MCQ belongs to Magic Mock Test Series — WBPSC AE Civil (Preliminary). Full tests include timed attempts, rank comparison and subject-wise analysis.