Section 6 Flashcards
1
Q
alkane with 1 carbon is called
A
methane
2
Q
alkane with 2 carbons are called
A
ethane
3
Q
alkane with 3 carbons are called
A
propane
4
Q
alkane with 4 carbons are called
A
butane
5
Q
alkane with 5 carbons are called
A
pentane
6
Q
alkanes with 6 carbons are called
A
hexane
7
Q
with what suffix do alkanes end?
A
-ane
8
Q
what is the general formula of alkanes?
A
CnH2n+2
9
Q
what are characteristics of alkanes?
A
- same chemical properties
- trend in physical properties
- same general formula
- same functional group
- single bonds
10
Q
what is the suffix when naming side chains (alkyl groups)
A
-ane is replaced with -yl
e.g. methyl, ethyl
11
Q
how do we number the C atoms of the main chain?
A
- start from the end from which a side chain first appears
- the position number is as LOW as possible
- if there are several possibilities: the alkyl group with alphabetic precedence receives the lower number
12
Q
draw the structure of 2,4-dimethyl hexane
A
13
Q
how do we name alkanes?
A
position number - side chain - main chain
14
Q
generla formula of alkyl groups
A
CnH2n+1
15
Q
general formula of alkenes
A
CnH2n
16
Q
what is a hydrocarbon?
A
a compound of hydrogen and carbon only
17
Q
what does an incomplete combustion produce?
A
carbon monoxide
soot (carbon particles)
water
18
Q
when does an incomplete combustion reaction take place?
A
when there is not enough oxygen around
19
Q
refinery gas
A
- used for cooking and heating
- raw material for industrial purposes
20
Q
gasoline
A
mostly a fuel for motors (cars, boats)
21
Q
kerosene
A
- fuel for aircrafts or heating
- solvent in paints
22
Q
diesel
A
- a fuel for large vehicles (cars, buses, train)
- fuel to generate electricity and heat
23
Q
fuel oil
A
- used as a fuel for ships and industrial heating
24
Q
definition of fuel
A
a fuel is a substance which releases heat energy when burned
25
why is CO (carbon monoxide) a toxic gas?
It binds with haemoglobin in the red blood cells and prevents oxygen from being transported
26
describe the composition of crude oil on a chemical level
a mixture of different hydrocarbons with a very different chain length and structure
27
describe and explain the trend in the boiling and melting points of the alkanes
the higher the number of C-atoms (the longer the hydrocarbon chain) the higher the boiling point of the alkanes
-> the longer the carbon chain the stronger the intermolecular forces
-> the more energy needed to overcome these
28
crude oil
a mixture of hydrocarbons - molecules made of only carbon and hydrogen
29
how are the different compounds in crude oil separated?
by fractional distillation
30
fractional distillation for crude oils
1) the oil is heated until most of it has turned into gas, which enter a fractionating column
2) as the substances that make up crude oil reach a part of the column where the temperature is lower than their boiling points, they condense
3) bubble caps stop the separated liquids from running back down the column and remixing
31
what will each fraction contain?
- each fraction contains a mixture of hydrocarbons with similar boiling points
- they might contain saturated or unsaturated hydrocarbons
32
the longer the hydrocarbons have...
- higher boiling points
- they condense and drain out of the column early on
33
the shorter hydrocarbons have...
- lower boiling points
- they condense and drain out much later on, near the top of the column where it's cooler
34
boiling point of Petrol / gasoline
70 degrees Celsius
35
boiling point of Kerosene
180 degrees Celsius
36
boiling point of Diesel
260 degrees Celsius
37
the longer the hydrocarbon chain...
- more viscous
- less volatile
- less flammable
- darker the hydrocarbon
38
why do bigger hydrocarbons evaporate more slowly at room temperature?
bigger molecules are more strongly attracted to their neighbours
39
volatile
describes how easily a substance vaporises
40
viscous
the resistance of particles in a fluid to flow or move
41
what is an example of a viscous liquid?
honey
42
give an example of a volatile liquid
gasoline
43
bitumen
surface for roads
44
name 4 fractions in the fractional distillation of crude oil
gasoline (petrol)
kerosene
diesel
bitumen
45
how is crude oil formed?
- formed naturally
- from remains of dead plants and animals in the sea which fell to the bottom
- layers of sediment formed on top of them
46
what type of resource is crude oil?
a finite, non-renewable resource
47
what is meant by the term homologous series?
a group of compounds that can all be represented by the same general formula
48
methane will react with bromine in the presence of UV light. what type of reaction is this?
substitution reaction
49
methane + bromine together with UV light will produce...
bromomethane + hydrogen bromine
50
draw the displayed formula; methane + bromine = bromomethane + hydrogen bromine
51
what type of reaction takes place when bromine water is added to an alkene?
an addition reaction
52
what do you expect to observe when an alkene is added to bromine water?
the solution would turn from orange-brown to a colourless solution
53
polymerisation
is the joining up of lots of little molecules (monomers) to make one big molecule (polymer)
54
what does LD-PE stand for? give one example
low density polyethene (plastic bag)
55
HD-PE
high density polyethene (plastic container, bottles)
56
what are the main uses of poly-propene?
bottle caps, boxes and storage containers
57
write the general reaction equation for the polymerisation of propene using the displayed formula
58
what is polychloroethene?
one of the hydrogen atoms in ethene is replaced by a chlorine
59
polymerising chloroethene gives you what?
polychloroethene
60
what's the formula of polychloroethene?
CH2=CHCl
61
what is tetrafluoroethene?
a molecule derived from ethene in which all four hydrogen atoms are replaced by fluorine
62
write the general reaction equation for the polymerisation of terafluoroethene using the displayed formula
63
what is the main use of poly-tetrafluoroethene?
brand name: Teflon
- non-sticking pans
- GoreTex in clothing
64
functional group of alcohols
65
functional group of alkenes
66
functional group of esters
67
functional group of carboxylic acids
68
what are the molecules that react to form an ester?
carboxylic acid + alcohol
69
draw the structure of 3-ethyl-2methyl pentane
70
2,2-dimethyl butane
71
2-methyl pentane
72
draw the repeat unit of the monomer
73
state four characteristics of the members of a homologous series
- same general formula
- similar chem properties
- trend in phys properties
- same functional group
74
If you shake an unknown organic compound with bromine water and the orange bromine water is decolourised, the compound contains what?
a carbon-carbon double bond
75
Note the reaction equation of the addition of Br2 to propene with displayed and molecular formulae
76
empirical formula
the simplest whole number ratio of atoms of each element in a compound
77
molecular formula
the actual number of atoms of each element in a molecule
78
displayed formula
shows how all the atoms are arranged and all the bonds between them
79
structural formula
shows the arrangement of atoms carbon by carbon, with the attached hydrogens
80
what is formed by joining up many monomers
addition polymers
81
why are addition polymers inert?
the carbon-carbon bonds in the polymer chain are very strong and aren't easily broken
82
inability of addition polymers to biodegrade
-carbon-carbon bonds are strong, meaning that it takes a really long time for addition polymers to biodegrade
- fill up landfill sites
- burning plastics can release toxic gases
83
what catalyst is used for cracking?
Silica or alumina
84
what does cracking produce?
an alkane is heated until it vaporises and breaks down into a short-chain alkane and alkene, when it comes into contact with the catalyst.
85
what does an incomplete combustion produce?
carbon dioxide, water, carbon monoxide, and carbon (soot)
