pollutants and gas tests Flashcards
complete combustion info
- requires a lot of oxygen
- C atom in METHANE is OXIDISED to form carbon dioxide
- H atoms OXIDISED to become WATER VAPOUR
carbon monoxide
toxic
formed if the amount of oxygen for complete combustion is reduced
sulfur dioxide
formed when sulfur atoms in fuels are OXIDISED
causes breathing problems in humans
dissolve in rain to form acid rain
oxides of nitrogen facts
- produced inside engines
- high temperatures cause nitrogen and oxygen from the air to react
- causes breathing problems in humans
dissolve in rain to form acid rain
particulates effect on health
particles of carbon (soot) and unburned hydrocarbons
can damage human health (increase risk of heart + lung disease)
global dimming
when particulates reduce the amount of energy from the sun that reaches the earth’s surface
(may be affecting rain patterns)
GAS TEST
chlorine
dampen blue litmus paper and put in test tube
if chlorine is present, litmus turns white
CHLORINE gas test
paper may turn red before turning white
this is because Cl dissolves in the water on the damp litmus + forms HCl
then it turns white as it is bleached by the Cl
CHLORINE gas test
safety
Cl is poisinous
- wear a mask
OR - do it in a fume cupboard
GAS TESTS oxygen
- place glowing splint in test tube of sample gas
- if oxygen present, splint relights
this is because burning requires oxygen
GAS TESTS hydrogen
- burning splint into test tube
- when close enough, squeaky pop heard
heat energy from flame causes hydrogen to burn with oxygen in the air, forming water
GAS TESTS carbon dioxide
- CO2 in one tube, aq solution of calcium hydroxide in another
- bubble gas sample through the calcium hydroxide (LIMEWATER)
- if CO2 present, solution goes cloudy
CaCO3 is a solid, its solid particles make the solution appear cloudy
