Made Possible by Sir anwar Chemistry Of Environment MUHAMMAD MIKHAIL IMAN BIN ZAABA 3 AL RAZI -1-
Contents 10.1 10.3 10.2 WA TE R A I R Q U A L I T Y A N D C L I M A TE FE R T I L IZE R S -2-
-In Presence of water, anhydrous Cobalt (II) chloride turns from B L U E P I N K 10.1Water Describe chemical tests for the presence of water using anhydrous cobalt(II) chloride and anhydrous copper(II) sulfate. 1. -In presence of water anhydrous Copper (II) Sulphate turns from Formula: CoCl2 (s) + 6H2O (l) = CoCl2.6H2O Formula: CuSO4 (s) + 5H2O (l) CuSO4.5H2O (s) WH I TE B L U E
-WA TE R H A S A B O I L I N G P O I N T O F 100 C A N D M EL T I N G P O I N T O F 0 C 10.1Water 2. Describe how to test for the purity of water using melting point and boiling point. - M IXT U R ES H OWEVE R H A VE M A N Y D I F FE R E N T TE M P E R A T U R ES B E C A U SE T H E S U B S T A N C ES I N T H E M IXT U R E H A VE D I F FE R E N T B O I L I N G A N D M EL T I N G P O I N T S - T H E R EF O R E B A SE D O N T H I S TE M P E R A T U R E D A T A WE C A N K N OW T H E P U R I T Y O F WA TE R - F O R EX A M P LE: I M P U R I T IES C A N I N C R E A SE T H E B O I L I N G P O I N T O F WA TE R A N D D E C R E A SE T H E M EL T I N G P O I N T O F WA TE R
10.1Water 3. Explain that distilled water is used in practical chemistry rather than tap water because it contains fewer chemical impurities. -Distilled water is water that has gone through the distillation process i.e boiling turned to vapour and condensed back into water VS -Few impurities -High Purity -Suitable to be used in practical chemistry D I S T I L LE D WA TE R T A P WA TE R -More impurities -Not suitable for use in practical chemistry
N A T U R A L WA TE R F R O M D I F FE R E N T S O U R C ES M A Y C O N T A I N T H ESE S U B S T A N C ES : ( A ) D I S S O LVE D O XY G E N ( B ) M ET A L C O M P O U N D S ( C ) P L A S T I C S ( D ) SEWA G E (E) H A R M F U L M I C R O B ES ( F ) N I T R A TES F R O M FE R T I L I SE R S ( G ) P H O S P H A TES F R O M FE R T I L I SE R S A N D D ETE R G E N T S 10.1Water T H ESE S U B S T A N C ES C A N G ET I N T O P U R N A T U R A L WA TE R D U E T O F A L L WA S H I N G T H E S U B S T A N C ES I N T O R IVE R S B U T C A N A L S O B E D U E T O H U M A N A C T IVI T Y I .E P O L L U T I O N , I N D U S T R Y 4. State that water from natural sources may contain substances,
10.1Water 5. State that some of these substances are beneficial, including: (a) dissolved oxygen for aquatic life (b) some metal compounds provide essential minerals for life A Q U A T I C L I FE N EE D D I S S O LVE D O XY G E N F O R R ES P I R A T I O N M ET A L C O M P O U N D S -WA TE R C O N T A I N S M I N E R A L S L I K E C A L C I U M A N D M A G N ES I U M WH I C H A R E ES SE N T I A L F O R L I FE.
10.1Water 6. State that some of these substances are potentially harmful, including: (a) some metal compounds are toxic (b) some plastics harm aquatic life (c) sewage contains harmful microbes which cause disease (d) nitrates and phosphates lead to deoxygenation of water and damage to aquatic life M ET A L C O M P O U N D S L I K E LE A D C A N B E VE R Y H A R M F U L T O O U R H E A L T H . P L A S T I C S I N T H E WA TE R C A N B E H A R M F U L T O SE A A N I M A L S . O U R SEWA G E C A N C O N T A I N M A N Y H A R M F U L M I C R O B ES T H A T C O U L D A F FE C T O U R H E A L T H FE R T I L IZE R S C A N C A U SE T H E G R OWT H O F P L A N T L I FE WH I C H C A N D E O XY G E N A TE T H E WA TE R
10.1Water 7. Describe the treatment of the domestic water supply in terms of: (a) sedimentation and filtration to remove solids (b) use of carbon to remove tastes and odours (c) chlorination to kill microbes SE D I M E N T A T I O N A N D F I L T R A T I O N Sedimentation- the process where dirt mud and sand fall to the bottom of the tank Filtration- Using layers of sand and gravel filters, many particles can be trapped and filtered from the water C A R B O N Water is passed through charcoal (carbon) to remove odour and taste C H L O R I N E Chlorine is added in small amounts to kill bacteria and other microorganisms
10.2 Fertilizers 1. State that ammonium salts and nitrates are used as fertilisers 2. Describe the use of NPK fertilisers to provide the elements nitrogen, phosphorus and potassium for improved plant growth A M M O N I U M S A L T S I N FE R T I L IZE R S Ammonium salts are used in the making of fertilizers. They are used in different proportions to achieve different purposes Example: Ammonium nitrate, NH4NO3 Ammonium phosphate, (NH4)3PO4 Potassium sulfate, K2SO4 U SES O F N I T R O G E N , P H O S P H O R U S A N D P O T A S S I U M Nitrogen- makes chlorophyll and protein which helps to maintain healthy leaves Phosphorus- Promotes healthy plant roots Potassium- Promotes healthy flower and fruit growth
10.3 Air Quality and Climate 1. State the composition of clean, dry air as approximately 78% nitrogen, N2, 21% oxygen, O2 and the remainder as a mixture of noble gases and carbon dioxide, CO2 C O M P O S I T I O N O F A I R
10.3 Air Quality and Climate 2. State the source of each of these air pollutants, 3. State the adverse effect of these air pollutants, limited to: (a) carbon dioxide (b) carbon monoxide (c) methane (d) oxides of nitrogen (e) sulfur dioxide C A R B O N D I O XI D E C O 2 Source: CO2 is produced by the burning of carbon fuels like fossil fuels Formula: CH4 + O2 → CO2 + 2H2O Adverse effect: Global warming which can lead to climate change C A R B O N M O N O XI D E C O Source: CO is produced by incomplete burning of fossil fuels. Formula: C8H18 + 9O2 → 5CO + 2CO2 + 9H2O Adverse effect: Toxic to humans, can affect haemoglobin in the blood
10.3 Air Quality and Climate M ET H A N E C H 4 Source: CH4 is produced from waste gases from digestive process in animals and vegetable decomposition Adverse effect: Can cause global warming which can lead to climate change O XI D ES O F N I T R O G E N Source: These oxides are produced in places where oxygen and nitrogen meet at high temperatures like car engines Adverse effect: Can cause photochemical smo. Can also dissolve in rain to produce acid rain Source: Combustion of fossil fuels containing sulfur compounds Adverse effect: Can also dissolve in rain to produce acid rain S U L F U R D I O XI D E S O 2
using renewable energy sources like solar and wind instead of fossil fuels could reduce emissions reducing number of livestock animals would decrease methane emissions planting more trees so that more carbon dioxide can be removed from our atmosphere 10.3 Air Quality and Climate C L I M A TE C H A N G E 4. State and explain strategies to reduce the effects of these environmental issues, limited to: (a) climate change (b) acid rain A C I D R A I N Use of Catalytic convertors to filter oxides of nitrogen from being released into the atmosphere Use of fuels which are low in sulphur and Flue gas desulphurisation which involves reacting sulphur dioxide with calcium dioxide to remove it
Endothermic reaction because energy is absorbed from the environment into the chloroplast to make glucose The reaction is between carbon dioxide + water to produce glucose + oxygen Chlorophyll provides light energy to help in the reaction 10.3 Air Quality and Climate P H O T O S Y N T H ES I S 5. Describe photosynthesis as the reaction between carbon dioxide and water to produce glucose and oxygen in the presence of chlorophyll and using energy from light
10.3 Air Quality and Climate F O R M U L A O F P H O T O S Y N T H ES I S 6. State the word equation for photosynthesis, carbon dioxide + water → glucose + oxygen
When the sun emits energy in the form of radiation some of it is reflected back in space most of it is absorbed and re-emitted from the Earth’s surface However greenhouse gasses like methane and carbon dioxide absorb the energy and is re-emmited in all directions this reduces the thermal energy lost into the atmosphere thus increasing temperature on Earth. This is the Greenhouse effect 10.3 Air Quality and Climate T H E G R EE N H O U SE EF FE C T 7. Describe how the greenhouse gases carbon dioxide and methane cause global warming, limited to: (a) the absorption, reflection and emission of thermal energy (b) reducing thermal energy loss to space
Compounds like NO and NO2 are formed when oxygen and nitrogen react at high temperatures similar to the conditions of car engines This is why cars are fitted with Catalytic Convertors 10.3 Air, Quality and Climate O XI D ES O F N I T R O G E N I N E N G I N ES 8. Explain how oxides of nitrogen form in car engines and describe their removal by catalytic converters, e.g. 2CO+2NO→2CO2 +N2 C A T A L Y T I C C O N VE R T O R S Catalytic convertors contain many transition metal catalysts like platinum The metal catalyst are in the shape of a honeycomb to increase surface area A series of redox reactions occurs which neutralises the pollutants 2NO + 2CO → N2 + 2CO2
10.3 Air Quality and Climate T H E S Y M B O L E Q U A T I O N F O R P H O T O S Y N T H ES I S 9. State the symbol equation for photosynthesis, 6CO2 + 6H2O → C6H12O6 + 6O2
Thank You “EVE R Y G R E A T B E G I N I N G N EE D S A G R E A T E N D I N G