Civil Engineering MCQAE Level Civil Engineering
In natural water, hardness is due to the presence of
Environmental EngineeringEnvironmental EngineeringMEDIUM
Choose the correct answer
A
Ca²⁺ and Mn²⁺
B
Na⁺ and K⁺
C
Ca²⁺ and Fe²⁺
D
Ca²⁺ and Mg²⁺
Correct Answer
D. Ca²⁺ and Mg²⁺
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Hardness is caused mainly by calcium and magnesium ions.
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This MCQ belongs to WBPSC AE Previous Years Questions Series. Full tests include timed attempts, rank comparison and subject-wise analysis.