Detergents clean well in hard water, but soaps do not. Why?

Detergents remove the calcium and magnesium from the water by boiling itCorrect answerYour answerDetergents do not form an insoluble scum with calcium and magnesium ionsCorrect answerYour answerDetergents are acids that dissolve the hardnessCorrect answerYour answerSoaps dissolve only in hot waterCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer B

Correct answer: B

Soap molecules combine with calcium and magnesium ions to make an insoluble scum, so the soap is used up and little lather forms.
Detergent molecules stay dissolved with these ions, so they keep cleaning.

Worth noting

Detergents do not soften the water; they simply do not react with the hardness.

Concept: Soaps and detergents in hard water
Typical timeTypical: 90 s
Your timeYours: —

The rule this testsCompounds in everyday life

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Detergents clean well in hard water, but soaps do not. Why?

Explanation