Community Service Learning Water Purification Project

Try these questions

5 questions from this lesson’s quiz. Start the lesson to answer them and see the right answers.

1. 1. In a homemade water filter, which order of layers, from TOP to BOTTOM, is correct?

   • A. Fine sand, charcoal, gravel, cotton wool
   • B. Gravel, sand, charcoal, cotton wool
   • C. Charcoal, gravel, cotton wool, sand
   • D. Cotton wool, charcoal, sand, gravel

2. 2. Wanjiru filters muddy river water through sand and charcoal. The water looks clear. Why should she still boil it before drinking?

   • A. Boiling makes the sand dissolve
   • B. Boiling kills microscopic pathogens that pass through the filter
   • C. Boiling adds minerals to the water
   • D. Boiling removes the charcoal smell only

3. 3. What term describes the trapping of dissolved particles onto the surface of a solid such as activated charcoal?

   Type your answer in the lesson.

4. 4. Which separation method is most suitable for removing coarse sand and floating plant debris from muddy river water?

   • A. Sublimation
   • B. Paper chromatography
   • C. Filtration
   • D. Magnetic separation

5. 5. Which of these is the best way to store boiled drinking water at home to prevent recontamination?

   • A. In an open basin, dipping a cup to scoop it out
   • B. In a covered container with a tap or a clean long-handled ladle
   • C. In an uncovered bucket on the ground
   • D. In any container, since boiling makes water safe forever

More in Introduction to Integrated Science

• ▸Laboratory Apparatus Heating and Mass Measurement
• ▸Optical Instruments and Volumetric Glassware
• ▸Classification of Mixtures and Purity Determination
• ▸Physical Separation Techniques for Mixtures
• ▸Acids, Bases, and Natural Indicators
• ▸Acids, Bases and the pH Scale
• ▸Introduction to Laboratory Safety and Rules
• ▸Laboratory Design, Layout, and Safety Installations

See every Grade 7 Integrated Science lesson →