cracking hydrocarbons Flashcards
1
Q
what is cracking
A
longer chain molecules can be broken down into shorter more useful hydrocarbons
2
Q
two main methods of cracking are
A
steam cracking and catalytic cracking
3
Q
during steam cracking:
A
- hydrocarbons are mixed with steam
- heated to 850°
4
Q
during catalytic cracking:
A
- hydrocarbons are heated until they vaporise
- vapour is passed over a hot aluminium oxide catalyst
- a thermal decomposition reaction then takes place
5
Q
thermal cracking uses
A
high temp and pressure
6
Q
catalytic cracking uses
A
low temp and pressure using catalyst
7
Q
SSS for bromine water
A
- single bond (alkane)
- saturate
- satsuma colour, orange to colourless
8
Q
what does saturated mean
A
lots of hydrogens
9
Q
formula for alkene
A
CnH2n
10
Q
what does an alkane contain
A
single bonds
think of how alkAne ((a)) comes first in alphabet, so it’s single whereas as alkEne ((e)) comes later
11
Q
what are alkane used for
A
fuels
12
Q
what are alkenes used for
A
polymers and manufacture of plastics
13
Q
alkenes have
A
double bonds
