In an investigation. Equal amounts of soap was added to equal amounts of water samples W and Z obtained from different sources. The following observations...

In an investigation. Equal amounts of soap was added to equal amounts of water samples W and Z obtained from different sources. The following observations were made:
(i) W formed lather.
(ii) Z formed suspended particles.
Which of the following statements about W and Z is NOT CORRECT?
A. W may have fewer minerals.
B. Z may form lather after boiling.
C. W can form scales in kettles.
D. Z wastes soap when washing.

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The correct answer is C. W can form scales in kettles.

Soft water does not form scales on kettles.

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sharon kalunda answered the question on July 30, 2019 at 09:24

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