In an experiment, soap solution was added to three separate samples of water. The table below shows the volumes of soap solutions required to form lather with 1000cm³ of each sample of water before and after boiling.

In an experiment, soap solution was added to three separate samples of water. The table below shows the volumes of soap solutions required to form lather with 1000cm³ of each sample of water before and after boiling.

a) Which water sample is likely to be soft? Explain
b) Name the cause of change in the volume of soap solution used in sample III

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a) Sample II: ... because it requires little soap to lather.

b) Sample III has temporary hardness, which is removed by boiling

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johnmulu answered the question on April 21, 2017 at 06:54

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