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CHEMISTRY

JAMB 2004 - Question 15

Chemistry 2004 JAMB Past Questions - Question 15: Hardness of water is caused by the presence of the ions of

Choose the correct answers from the options given.

Hardness of water is caused by the presence of the ions of

A: magnesium and silver

B: calcium and magnesium

C: sodium and potassium

D: calcium and sodium

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Correct Answer

Explanation

The hardness of water is primarily caused by the presence of calcium (Ca2+) and magnesium (Mg2+) ions. These ions can form insoluble compounds with soap, leading to reduced lathering and the formation of soap scum.