Unit 10 - Chemistry of the environment

Dry Cobalt(II) chloride paper will change from blue to pink if exposed to water

Copper(II) sulfate will change from white to blue if exposed to water

Investigating freezing and boiling points

• Dissolved oxygen - need for aquatic animals • Metal compounds - needed for plants but can be toxic • Plastics - harmful for aquatic animals • Sewage and harmful microbes - can causes diseases • Nitrates and phosphates from fertilizers - eutrophication

• Water from a lake passes through a screen to prevent large solids going through • Water enters a sedimentation for a while for insoluble heavy solids to fall to the bottom • Water passes through another filter to remove small insoluble solid impurities • Water is pushed through carbon particles at high surface area to bond and remove any unwanted molecules that could affect taste and smell • Chlorine gas is bubbled into the water to kill bacteria and destroy viruses

• 45% mineral • 5% organic • 20-30% water • 20-30% air

Breaks down diatomic triple-bonded N2 in air to nitrogen that plants can use

• Nitrogen • Phosphorus • Potassium

• 78% Nitrogen • 21% Oxygen • 1& noble gases - argon (0.93%) • 0.04% Carbon dioxide

• Carbon dioxide • Methane

Increasing concentrations of carbon dioxide and methane molecules in the atmosphere are absorbing some wavelengths of light instead of being reflected which causes the average temperature of the atmosphere to rise

• Oxides of nitrogen • Sulfur dioxide

Particles of solid or liquid material that are small enough to remain airborne

• Carbon monoxide + Nitrogen oxide –> Carbon dioxide + Nitrogen • 2CO + 2NO –> 2CO2 + N2

• Source - complete combustion of carbon-containing fuels • Effects - increases global warming • Solutions - planting more trees, burning less fossil fuels by using renewable energy

• Source - Incomplete combustion of carbon-containing fuels • Effects - Toxic gas • Solutions - Catalytic converters on cars

• Source - burning carbon-containing fuels • Effects - respiratory problems and increases amounts of cancer • Solutions - air filters

• Source - Decomposition of plants & waste product of animals • Effects - Increases global warming • Solutions - Reduce livestock farming & eating less meat and dairy foods

• Source - inside car engines where oxygen and nitrogen react • Effects - respiratory problems, forms acid rain, produces photochemical smog • Solutions - Fitting catalytic converters in cars

• Source - burning sulfur-containing fossil fuels (coal) • Effects - forms acid rain • Solutions - Burning low sulfur fuels instead & flue gas desulfurization by passing gases through solid calcium oxide