Chapter 9 Flashcards
what are some properties of crude oil
finite resource
a mixture of hydrocarbons
seperated by fractional distillation
describe how crude oil is seperated into fractions
- the oil is heated to about 400°C until it vaporises
- the vapours enter a fractionating column which has a temperature gradient (cooler at the top, hotter towards the bottom)
- the vapours then condense when they reach a height where the temperature matches their boiling point
- longer hydrocarbons have higher boiling points so they condense lower in the coloumn where it is hotter
word equation for the combustion of hydrocarbons
hydrocarbon + oxygen —-> carbon dioxide + water
draw ethane (alkane)
functional group of alkanes
does not have one
ending of alkanes
-ane
general formula of alkanes
CnH2n+2
what happens when alkanes react with bromine water
it stays orange
draw ethene
functional group of alkenes
C=C
ending of alkenes
-ene
general formula of alkenes
CnH2n
what happens when alkenes react with bromine water
it goes colourless
what are hydrocarbons
a molecule made up of hydrogen and carbon atoms ONLY
what are saturated hydrocarbons
hydrocarbons that contain only single bonds between the carbon atoms (e.g alkanes)
what is the moles formula
mass = Mr x moles
what does Mr stand for
relative atomic mass
name the process which produces smaller hydrocarbon molecules from heavy fuel oil
cracking
what are the conditions needed for cracking
high temperature and steam/catalyst
crack octane
