Chemistry of the Environment
暂无描述。系统推荐的高质量记忆内容，适合每天坚持背诵学习。
卡片预览 (24 张)
What colour does anhydrous copper(II) sulfate turn in presence of water?
Blue
What colour does anyhydrous cobalt(II) chloride turn in presence of water?
Pink
Define the term Pure Substance
A pure substance consists of a single element or compound only
Describe the physical test used to determine whether a sample of water is pure
To check the boiling point of water if it is a 100 degrees celsius
Effect of impurities on the boiling point of water
Increase the boiling point
Name the piece of apparatus used to check the boiling point of water
Thermometer
Effect of impurities on the melting point of water
Lower the melting point
Why is distilled water used in practical chemistry?
Due to its high purity, which prevents interference with chemical reactions
List 4 substances that may be found in water from natural sources
• Dissolved Oxygen • Metal Ions • Plastic • Sewage
What are 2 beneficial substances found in water from natural resources?
• Dissolved Oxygen • Some Metal Compounds
Why is dissolved oxygen beneficial in water?
It is essential for aquatic life
Name 2 potentially harmful substances found in water from natural resources
• Sewage • Some Metal Compounds
What are nitrates and phosphates in water often sourced from?
Fertilizers & Detergents
True or False? All metal compounds in water are harmful
False
Define eutrophication
Process where excess nutrients in water promote plant growth, leading to deoxygenation and damage to aquatic life
What is the first step in the purification of water?
Filtration to remove large particles
True or False? Distillation is used in water purification
False
What happens during sedimentation in water treatment?
Allows heavy particles to settle at the bottom of the water treatment tanks
What is the purpose of Chlorination?
To disinfect water and kill bacteria and pathogens
What type of impurities does untreated water contain?
Soluble and Insoluble Impurities
List 3 examples of soluble impurities in water
• Dissolved Calcium • Metallic Compounds • Inorganic Pollutants
What are the 3 main steps of water treatment?
• Filtration • Sedimentation • Chlorination
Why is carbon (charcoal) used in water treatment?
To remove unpleasant taste and odors
What does NPK stand for in fertilisers
Nitrogen, Phosphorus, Potassium