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The weight of precipitate in each solution was found using vacuum filtration. The contents of each cylinder were poured through a filter and the liquid was vacuumed out. The precipitate left on the filter paper was then weighed.

Observations

After allowing the cylinders to stand for a few days, most of the precipitate settled to the bottom, but some did float as a film on the very top of the solution. Also, some flocs of precipitate could be seen floating throughout the solution.

Results & Discussion

For the first three days, the height of precipitate in the bottom of each cylinder increased. At day four, the amount of precipitate did not increase from day three.

Using that after 3 days, no more precipitate settles out, gives a good estimate of time to wait before using the calcium hypochlorite solution. Waiting 3 days to use the solution and pouring out only the liquid at the top of solution should decrease the amount of precipitate in the system and help to eliminate clogging.