Ch 17 - (Chemistry of our environment)
No description yet. This curated deck is ready for daily study.
Card preview (24)
What is used to test for water?
• Cobalt (II) chloride • Copper (II) sulfate
How is the test for cobalt chloride done?
using cobalt chloride paper
what is the word equation for cobalt (II) chloride?
Anhydrous cobalt (II) chloride + water –> <– hydrated cobalt (II) chloride
what is the symbol equation for cobalt (II) chloride?
CoCl2 (s) + 6H2O (l) –> <– CoCl2.6H2O (s)
what is the word equation for copper (II) sulfate?
Anhydrous copper (II) sulfate + water –> <– hydrated copper (II) sulfate
what is the symbol equation for copper (II) sulfate?
CuSO4 (s) + 6H2O (l) –> <– CuSO4.5H2O (s)
What is the positive test for water in copper sulfate and cobalt chlroide?
cobalt (II) chlroide: Blue to pink Copper (II) sulfate: White to blue
What can be used to test for the purity of a substance?
Melting point and boiling point
what is distilled water?
Water that has been heated to form a vapour and has been condensed back to a liquid Contains less impurities
Why is distilled water used in practical impurities
High purity
What do we use water for?
• Domestic uses - drinking, cooking, gardening • Agriculture use - Frink for animals and crops • Industrial use - Solvent, coolant
Where is water found?
Natural sources as lakes, tigers and underground water sources
What is a rock that stores water called?
Aquifer
what does water from natural sources come from?
• dissolved oxygen • metal compounds • plastics • sewage • harmful microbes • nitrates from fertilizers • phosphates from fertilizers and detergents
What are examples of beneficial substances in water?
• Dissolved oxygen - essential for aquatic life • Metal compounds - essential minerals for life, magnesium and calcium
What are examples of harmful substances in water?
• Metal compounds - toxic, aluminum and lead • Plastic - harmful to aquatic life • Sewage - harmful microbes • Nitrate & phosphate fertilizers - promotes growth which leads to deoxygenation of water.
What does unreacted water contain?
Soluble and insoluble impurities
What do soluble and insoluble impurities include?
Insoluble - soil, pieces of plants, organic matter Soluble - dissolved calcium, metallic compounds, inorganic pollutants
What is the water treatment process?
• Water is pumped into sedimentation tanks where water is allowed to stand for a few hours • Mud sand particles fall to bottom of tank due to gravity, called sedimentation • Filtration - removes smaller particles by passing water through layers of sand and gravely trapped in filter • Water is passed through carbon (as charcoal) to remove taste and odours • Bacteria & microorganism removed by chlorination where chlorine is added to water
what’s the examples of bacterial diseases caused by untreated water?
Cholera and typhoid
What elements do fertilizers contain?
nitrogen, potassium, phosphorous (NPK)
What is the use of NPK in fertilisers?
• Nitrogen - makes chlorophyll and protein • Potassium - promotes growth & healthy fruit and flowers • Phosphorous - healthy roots
What are the fertilizer compounds that contain water soluble ions?
• Ammonium ions (NH4+) & nitrate ions (NO3-) • phosphate ions (PO43-) • potassium ions (K+)
What do common fertilizers compound include?
Ammonium nitrate (NH4NO3) Ammonium phosphate (NH4)3PO4 Potassium sulfate (K2SO4)