1Polarity of alkanes?
Non polar as electronegativity between H and C is similar
2Trend of boiling pt as carbon length increases?
Increases as the strength and quantity of van der waal forces increases
3Why do branched have lower boiling pts than straight
Same logic as unsaturated fatty acids
4Solubility?
Cant dissolve in water as its non polar
5What is crude oil?
mixture of mostly branched and linear alkanes and impurities
6how does fractional distillation work?
1)Crude oil is heated in a furnace to make vapour.
2)The vapour passes into the column.
3)Columns temperature decreases as you go up
4)Vapours goes up the tower until reaching a tray cooler than their boiling pt
5)Vapour condenses and is collected and piped off
7how to memorise fractions from up to bottom?
Good -Gasses
People - petrol
Kick - kerosene
Delusional -diesel
Lorries - lubricating oil
For - fuel oil
Banter - bitumen
8Products produced from cracking
shorter alkanes
alkenes - chemical feedstock / raw material
9thermal cracking?
High temperatures of 700 -1200 K and up to 7000kPa
C-C bond breaks in a way initially forming free radicals
Produces high proportions of alkenes
10Catalytic cracking:
Lower temps of 720K and pressures around 101kPa but uses honeycomb zeolite with huge SA
Produces branched alkanes( good for petrol) cycloalkanes and aromatic compounds
11what can incomplete combustion produce?
CO + H20 OR
C + H20
12Pollutants produced via combustion;
CO2 AND H20 - Greenhouse gases
CO - toxic and flammable
C - respiratory issues and global dimming
Unburnt hydrocarbons - smog and greenhouse gases
SO2 + NO - respiratory issues and acid rain
13Why is complete better than incomplete
More efficient and cheaper
14what are catalytic converters
its in the exhaust system coated with honeycomb shaped platinum/ rhodium etc
Converts CO +NO to CO2 +N2
Hydrocarbons to CO2 + H20
15Whats flue gas desulfurisation
CaO + H20 is sprayed over flue gas(contains SO2) which forms gypsum
CaSO4.H20
CaCO3 can also be used