Question
Which of the following ions are responsible for hardness of water?
MHT CET
Chemistry
Hydrogen
2026
MHT CET 2026 (13 April Shift 2)
MHT CET Chemistry Question (2026) — Solution
Options
- A. Ag ^+, Au ^ 3+ ions
- B. Hg ^ 2+ , Pb ^ 2+ ions
- C. Ca ^ 2+ and Mg ^ 2+ ions.
- D. As ^ 3+ , CN ^-
Answer
C. Ca ^ 2+ and Mg ^ 2+ ions.
Step-by-step solution
Hardness of water is primarily caused by the presence of soluble salts of calcium and magnesium, such as their bicarbonates, chlorides, and sulfates. Therefore, Ca ^ 2+ and Mg ^ 2+ ions are responsible for the hardness of water. Answer: Ca ^ 2+ and Mg ^ 2+ ions.
Related: Chemistry — Hydrogen · All PYQ Banks