in an experiment, soap solution was added to three separate samples of water. The table below shows the volumes of the soap solutions required to form lather with #1000cm^3# 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

Answer:

a)Sample II-because it requires less soap to lather
b)Sample III has temporary hardness which is removed by boiling.

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