Water and its Properties

Flashcards about testing water, water purity, natural water sources, and water purification.

Test with anhydrous cobalt(II) chloride

A test for water where anhydrous cobalt(II) chloride changes from blue to pink.

Test with anhydrous copper(II) sulfate

A test for water where anhydrous copper(II) sulfate changes from white to blue.

Purity of water

Pure water melts at 0°C and boils at 100°C. Impurities will lower the melting point of ice, increase the boiling point of water, and cause melting and boiling to take place over a range of temperatures.

Distilled water in practical chemistry

Tap water contains dissolved solids and impurities, while distilled water consists of only water molecules, providing more accurate results in practical chemistry.

Beneficial substances in natural water sources

Dissolved oxygen, metal compounds like aluminum, calcium, and potassium salts.

Potentially harmful substances in natural water sources

Toxic metal compounds, plastics, sewage, nitrates, and phosphates.

Screening (water purification)

Metal grids remove large solids like leaves and twigs.

Coagulants added (water purification)

Coagulants such as aluminum sulfate and iron (III) chloride are added to clump fine particles.

Sedimentation (water purification)

Clumped particles settle to the bottom of the tank.

Filtration (water purification)

Powdered carbon removes unpleasant tastes and odors; water Seeps through sand and gravel to remove any remaining fine particles.

Chlorination (water purification)

Chlorine is added to kill microbes, preventing water-borne diseases.