Clean Drinking WaterUsing the Scientific Method
• Please see the following six slides (handouts)
to engage students in an experiment related
to the video.
Step 4: Testing hypothesis 1  Upgrade diversion structures to
improve the efficiency of water delivery systems
Materials needed:
– 2 100mL beakers of water
– 2 100mL water
– 2 buckets that are larger than the beakers
– A 4x6” piece of stiff cardboard or plastic
– A 4x6” piece of flexible paper
– A 100mL graduated cylinder to measure water
Step 4: Testing hypothesis 1  Upgrade diversion
structures to improve the efficiency of water delivery
systems
Methods:
1. Measure out 100mL of water in each beaker.
2. Label the buckets Rigid and Flexible
3. Over a sink, pour one of the beakers into the
Rigid bucket using the cardboard as a funnel.
4. Pour the other beaker into the Flexible bucket
using the flexible paper.
5. Using the graduated cylinder, measure the
amount of water that is in each bucket.
Step 5: Analyzing the results and draw conclusions for
hypothesis 1  Upgrade diversion structures to improve the
efficiency of water delivery systems
1. Which system (Rigid or Flexible) had the most
water in the bottom bucket?
2. Why?
3. Which system would you rather use to collect
rain water?
4. How might you improve the design of the
diversion system to collect even more water?
Step 4: Testing hypothesis 2 Use the physical
properties of water to “clean” it using filtration.
Experiment on cleaning water using filtration:
• Materials:
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4 100 mL beakers
1/2 cup sugar
1/2 cup dirt
2 spoons
A stopwatch
Water to fill 2 of the beakers ¾ full
2 coffee filters
Pen and paper to record your findings
Step 4: Testing hypothesis 2 Use the physical
properties of water to “clean” it using filtration.
Methods:
1.
2.
3.
Label the beakers 1a, 1b, 2a, 2b.
Fill beaker 1a and 2a with ¾ full of water each.
Test 1:
1.
2.
3.
4.
In beaker 1a, add the cup of sugar and stir for 30 sec.
Pour the sugar/water solution into the empty beaker labeled 1b
through the coffee filter
Let it sit for 3 min and record what you see.
Test 2:
1.
2.
3.
In beaker 2a, dump the cup of dirt and stir for 30 sec.
Pour the dirt/water solution into the empty beaker labeled 2b
through the coffee filter.
Let it sit for 3 min and record what you see.
Step 5: Analyzing the results and draw conclusions for
hypothesis 1: Use the physical properties of water to “clean” it
using filtration.
1. Test 1:
1. Did anything get stuck in the filter when you poured the
sugar/water into beaker 1b? What do you think is in
beaker 1b? Is the water in beaker 1b clean? Would you
drink it?
2. Test 2:
1. Did anything get stuck in the filter when you poured the
dirt/water into beaker 2b? What do you think is in
beaker 2b? Is the water in beaker 1b clean? Would you
drink it?
3. What are your conclusions? Did filtration work?