Unit 10 - Chemistry of the environment Flashcards
steps to treating water? what do they do? (8 steps)
1) screen - filters big particles such as trash
2) coagulant is added - small soluble particles stick together and become insoluble
3) Sedimentation - air is blown through flotation tank to make coagulated particles float to the top (skimmed off)
4) filtration through sand
5) further filtration - charcoal or more sand to get rid of bad smell and taste
6) chlorine - kills bacterias and other microbes
7) fluride - help fight tooth decay
8) water is pumped to storage resevoir - to be pumped into homes
2 water tests? positive result?
anhydrous copper sulphate
-white powder –> blue
anhydrous cobalt chloride
-blue –> pink
air components?
78% nitrogen
21% oxygen
1% argon + other gases
6 common pollutants? symbols?
-carbon dioxide (CO2)
-sulfur dioxide (SO2)
-carbon (C)
-nitrogen monoxide (NO)
-carbon monoxide (CO)
-nitrogen dioxide (NO2)
5 air pollution sources?
-combustion of fossil fuels
–> transportation
–> electricity
–> energy (for industry)
-open waste burning (plastic)
-agriculture
–> animal’s burps
–> makes methane (CH4)
-Burning of fossil fuels
–> makes CO2, CO, C, SO2, NO2
-Decomposition
–> makes methane (CH4)
complete combustion formula?
CH4 + O2 –> CO2 + H2O
incomplete combustion formula?
CH4 –> CO + C
how is nitrogen dioxide made?
in internal combustion engines (car engines) as it has high temperature and high pressure and has both nitrogen and oxygen (in air)
effects of solid pollutants?
-dust
-carbon
-stops sunlight
–> no vitamin D
–> plants can’t photosynthesis, they die, everything dies
effect of acid rain?
-bridges collapse
-lungs have water which react with sulfur dioxide, makes sulfuric acid and melts lungs
-plants and animals get damaged
percentage of oxygen formula?
(difference in volume / volume at start) x 100
source of carbon dioxide?
-burning of fossil fuels
-respiration
-complete combustion of carbon - containing fuels
-sodium carbonate + HCl
-Thermal decomposition
–> breaking apart something because of acid or heat (1 reactant)
carbon and carbon monoxide source?
incomplete combustion of carbon containing fuels
sulphur dioxide source?
combustion of fossil fuels (that contain sulfur compounds)
nitrogen oxides source?
internal combustion (car engines)
methane source?
-waste gases from animal digestion
-decomposition of vegetation
fully combusted carbon forms?
CO2
fully combusted hydrogen forms?
H2O
carbon monoxide + oxygen?
carbon dioxide
hydrocarbon + oxygen?
carbon dioxide + water
nitrogen monoxide + carbon monoxide?
nitrogen + carbon dioxide
ways to reduce effects of climate change [4]
-plant trees
-decrease livestock farming
-decrease fossil fuels burning (use)
-increase use of hydrogen and renewable energy
–> solar panels
–> windmills
–> tidal (waves)
–> geothermal
–> hydrogen powered
–> nuclear
–> hydro-electric power
Concentration = ?
number of moles / volume
number of moles = ?
volume x concentration
what does sunlight do?
-heat up earth
-re-emitted (go back)
-straight back through cloud
-bounces off clouds
–> increases global temperature
–> greenhouse effect
why is distilled water used in practicals?
contains fewer chemical impurities than tap water
effect of carbon dioxide?
-higher levels = increased global warming (blanket forms) –> climate change (
-its a greenhouse gas –> greenhouse effect
effect of carbon monoxide
toxic gas
effect of particulates
increased risk of respiratory problems + cancer
effect of methane
-higher levels = increased global warming (blanket forms) –> climate change
-it’s a greenhouse gas –> greenhouse effect
effect of oxides of nitrogen
respiratory problems
acid rain
-water + nitrogen dioxide –> nitric acid
effect of sulfur dioxide
acid rain
-water + sulfur dioxide –> sulfuric acid
climate change examples
extreme weathers
-droughts
-tornados
-forest fires
-ice melts
-water level rises
-floods
–>affects health
reduce acid rain by?
-reduce emission of sulfur dioxide
–> use low sulfur fuels
–> use flue gas desulfurisation with calcium oxide at coal burning power stations
how do greenhouse gases cause global warming?
-absorption, reflection, emission of thermal energy
-reduces thermal energy loss to space
removal of nitrogen oxides by catalytic converters?
2CO + 2NO –> 2CO2 + N2
