Water Purification Experiments
Water purification experiments are a good way to learn and understand how water purification systems work as well as lead-ins to experiments or discussions regarding water conservation and the hydrologic cycle. The hydrologic cycle is the constant movement of water on and below the surface of the Earth
Other People Are Reading
-
Water Vapor
-
Experiments where water is heated and the water vapor is condensed and collected are useful to show that portion of the hydrologic cycle. Begin by heating water in a sealed container with only one outlet. As the vapor condenses from the outlet, through a hose and collects in a receiving container, this will demonstrate the ground-to-air-to-rain cycle.
Distillation
-
Repeat the experiment in Section 1 using a strong salt water heated source.
The water condensate collected in the receiving container will be drinkable. This will demonstrate the distillation process as used throughout the middle east to convert seawater into drinking water. -
Solar Distillation
-
Using a salt water container exposed to direct sunlight and a receiving container in a shaded or cooled location, the distillation experiment may be repeated. The pro; no electric or gas heating source and the con; much slower distillation rate, will be demonstrated regarding solar distillation.
Sedimentation
-
A significant contributor to U.S. fresh water purification is the sedimentation step. This may be demonstrated by taking a surface water source ( several gallons of river or lake water) and letting it settle.
The dirtier the source water, the more clear the multi-day settling process will become. Advanced classes may compare the settling rates of several samples where the fixed temperature of one sample is ten degrees or more higher than another sample. The pH (alkalinity) of a sample may be changed by adding an acid or a base solution to contrast to a standard sample which does not have the pH modified. In the end, drawing clear water from the top of the most-settled sample water and then examining the water for waterborne organisms under a microscope, will show the difference between clear water and drinking water.
Disinfection
-
The clear water samples taken from Section 4 should receive a small exposure (1, 5, and 10 drops) of chlorine bleach per pint of "clear" water to demonstrate disinfection. Follow-up examination with a microscope will show the differences in disinfected water versus clear water.
-
