Unit 8 Flashcards
(21 cards)
crude oil
- formed underground over millions of years
- ## made from hydrocarbons (mostly alkanes)
fractional distillation column
hotter at the bottom and cooler as you go up
longer hydrocarbons
- higher boiling points
- drain out of the column as liquids at the bottom
- liquids at room temperature
- high viscosity
shorter hydrocarbons
- lower boiling points
- near the top of the column
- gases at room temperature
- low viscosity
alkanes formula
Cn +H2n+2
complete combustion
hydrocarbon + oxygen - carbon dioxide + water
volcanos
- volcanos erupted releasing gases from inside the earth
- mainly carbon dioxide, steam, methane, ammonia
- then the water vapour condensed to form oceans
plants
- nitrogen gas entered atmopshere
- plants removed co2 and added o2
- co2 got locked up in fossil fuels and rocks
ozone layer
- build up of oxygen killed off animals
- but more complex organisms evolved
- oxygen created ozone layer which blocked the sun
chloride
white precipitate
bromide
cream precipitate
iodide
yellow precipitate
test for halide ions
add dilute nitric acid and then silver nitrate solution
test for carbonates
add dilute acid and test through limewater to see carbon dioxide
test for sulfate ions
add hydrochloric acid and add barium chloride solution
alkenes
- C=C functional group
- CnH2n
- unsaturated
natural polymers
- DNA
- amino acid
- carbohydrates
disposal of polymers in landfill sites
- difficult and expensive to recycle
- valuable land is used quickly
- non biodegradable
disposal of polymers by combustion
- toxic gases can be released
- co2 is produced
alcohols
- Cn H2n+1 OH
- OH functional group
carboxylic acids
- alcohols are oxidised
- COOH functional group
- Cn-1 H2n-1