Organic Chemistry Flashcards
1
Q
Term
A
Definition
2
Q
HYDROCARBONS
A
organic compounds composed only of two elements - carbon and hydrogen
3
Q
Main source of hydrocarbons
A
crude oil
4
Q
Two main classes of hydrocarbons
A
aliphatic and aromatic hydrocarbons
5
Q
Aliphatic hydrocarbons composition
A
carbon chains
6
Q
Acyclic aliphatic compounds
A
carbon chains are straight or branched
7
Q
Important families of acyclic aliphatic hydrocarbons
A
alkanes
8
Q
Cyclic aliphatic compounds
A
end carbon atoms of an acyclic carbon chain join together to form a ring
9
Q
Aromatic hydrocarbons composition
A
all cyclic compounds
10
Q
Basic cyclic structure of aromatic hydrocarbons
A
benzene ring
11
Q
Chief source of hydrocarbons
A
crude oil or petroleum
12
Q
Petroleum meaning
A
rock oil in Latin
13
Q
Petroleum state
A
dark
14
Q
Petroleum location
A
huge underground deposits in many parts of the world
15
Q
Substance usually found together with petroleum
A
Natural gas
16
Q
Petroleum composition
A
mixture of gaseous
17
Q
Natural gas composition
A
mainly methane
18
Q
Term
A
Definition
19
Q
Formation of crude oil and natural gas
A
formed from the remains of marine algae and animals
20
Q
Process of crude oil and natural gas formation step 1
A
tiny aquatic organisms died
21
Q
Process of crude oil and natural gas formation step 2
A
remains became covered by mud
22
Q
Process of crude oil and natural gas formation step 3
A
sediments piled up
23
Q
Process of crude oil and natural gas formation step 4
A
bacterial activity
24
Q
Movement of oil and gas
A
slowly moved to other areas through the tiny holes or pores in the porous rocks around them
25
Oil trap formation
seep upwards until they meet a non-porous layer of rocks and are trapped under it
26
World's oil reserve concentration
About three-fifths are in Asia
27
Other Asian countries rich in oil
China and Indonesia
28
Country with the next largest oil reserves
Russia
29
Remaining important oil reserve locations
northern and western Africa
30
Term
Definition
31
Crude oil extraction method
drilling deep holes or wells into the ground
32
Drilling equipment
rotary rig supported by a derrick
33
Crude oil and gas release
may shoot up into the air under high pressure when a well reaches an oil-bearing layer
34
Crude oil storage
large steel tanks
35
Crude oil transport
pipelines or tankers to oil refineries
36
Crude oil nature
not a single compound but a complex mixture of hydrocarbons
37
Crude oil value
so valuable that people call it 'black gold'
38
Crude oil state from the ground
just about useless
39
Crude oil processing
must undergo fractional distillation first
40
Fractional distillation process
separated into different portions called fractions
41
Fraction
contains several compounds
42
Fraction differentiation
different volatility
43
Oil refineries function
huge industrial complexes that separate
44
Oil refinery processing capacity
a few million tonnes of crude oil yearly
45
Oil refinery size
may occupy an area as large as a town
46
Industrial fractionation location
huge fractionating columns or towers
47
Fractionating column dimensions
each standing some 40 to 50 metres high and 7 metres across
48
Crude oil preheating temperature
about 400°C in an electric furnace where about 75% of the crude oil is vaporized
49
Fractionating column compartments
divided into several compartments by perforated plates called trays
50
Tray temperature gradient
each tray is a little cooler than the one below
51
Separation process in fractionating column
vapour cools
52
Separation based on boiling point
higher boiling points separate out in the lower trays
53
Further treatment of fractions
redistilled to improve purity and then further treated to obtain different liquid fuels and petrochemicals
54
Term
Definition
55
Experiment 28.1 objective
To fractionally distil crude oil and then test the properties of each fraction
56
Test-tube X filling
Fill to a depth of 3 cm with cotton wool
57
Cotton wool soaking
Pour about 3 cm3 of crude oil to soak the cotton wool
58
Test-tube X heating
Heat near the top end of the cotton wool with a low Bunsen flame
59
Distillate collection temperature range 1
between room temperature and 100°C in test-tube A
60
Test-tube A immersion
partially immersed in a beaker of cold water
61
Distillate in test-tube A
first fraction
62
Test-tube A next step
Remove and stopper
63
Distillate collection temperature range 2
100°C to 200°C in test-tube B
64
Distillate collection temperature range 3
200°C to 250°C in test-tube C
65
Residue removal
Remove the black sticky residue in test-tube X with a steel spatula
66
Observations
Note the colour and viscosity of each fraction and the residue
67
Tests
flammability
68
Flammability test method
slowly bringing a lighted match to a few drops of the fraction on a watch-glass and noting how easily it ignites
69
Nature of the flame test observations
sootiness and colour
70
Volatility test
temperature at which it evaporates
71
Conclusion
All oil fractions and residue burn easily and evaporate readily
72
Conclusion about lowest boiling-point fraction
burns completely producing a non-sooty flame
73
Conclusion about higher boiling-point fractions
burn less completely producing sooty flames
74
Term
Definition
75
Principal fractions obtained by fractional distillation of crude oil
Bitumen and other residues
76
Bitumen and other residues state
solid residues
77
Bitumen and other residues remaining temperature
above 500°C
78
Bitumen (pitch) use
surfacing roads and airfields
79
Other residues uses
fuel
80
Crude oil fractions
range from those with one carbon atom like methane to those with more than sixty carbon atoms
81
Fractions useful as fuels and raw materials in the chemical industry
low molecular mass and low boiling fractions (which make up 49% of the fractions)
82
Process to convert higher boiling hydrocarbon fractions to lower boiling ones
cracking
83
Main methods used in cracking
thermal cracking and catalytic cracking
84
Term
Definition
85
Fuel for Petrol Engines
Petrol engines
86
Petrol engine components
a number of cylinders (usually four) fitted with pistons
87
Piston movement
move up and down inside the cylinders
88
Each upward or downward movement of a piston
a stroke
89
Motor-car engine energy cycle
four-stroke energy cycle
90
Requirements for efficient working of the motor-car engine
fuel-air mixture must ignite at the correct stage in each cycle
91
Fuel properties
should possess the correct volatility and temperature of ignition for it to be burnt at the right time of the cycle
92
Effect of fuel being too volatile and having too low an ignition point
would be burnt prematurely
93
Consequences of knocking
reduces the efficiency of the motor-car engine and shortens its life
94
Effect of fuel not being volatile enough and having too high an ignition temperature
may not be burnt completely
95
Consequences of incomplete burning of fuel
Excessive black smoke and unburnt hydrocarbons are expelled from the car exhaust
96
Fuel that meets all the requirements necessary to power a motor-car engine
Petrol
97
Another name for motor-car engines
petrol engines
98
Modern petrol engines tendency
have a tendency to 'knock' if low-quality petrol is used
99
Petrol grade or quality measurement
according to a scale called the octane-number system
100
Petrol with a higher percentage of straight-chain hydrocarbons
causes more knocking than that containing a higher percentage of branched-chain ones
101
Octane number of a straight-chain alkane like heptane
0
102
Octane number of 2
2
103
Quality of any petrol rating
according to its octane number
104
Term
Definition
105
Determination of the octane number of petrol
the amount of knocking caused by the petrol
106
Example of octane number rating
a fuel with an octane number of 50 has a performance equivalent to a 50-50 mixture of heptane and 2
107
Petrol grading
Premium
108
Relationship between octane number and molecular mass of straight-chain hydrocarbons
the lower the molecular mass of the hydrocarbon
109
Octane number of some fuels
Some fuels which are superior to 2
110
Natural gas composition
gaseous hydrocarbons
111
Former treatment of natural gas
burnt off as waste at the oil wells
112
Current treatment of natural gas
piped for industrial and domestic use
113
Components of natural gas sold as bottled gas
butane and propane which liquefy readily under pressure
114
Natural gas use in Nigeria
fuel for heavy-duty vehicles and engines
115
Nigeria's proposal
to set up a Liquefied Natural Gas Plant to increase its natural gas consumption at home and also to export the gas
116
Term
Definition
117
Petrochemicals
many organic compounds produced from petroleum and natural gas
118
Examples of petrochemicals
ethanol
119
Uses of petrochemicals
make large-molecule organic compounds like plastics
120
Definition of petrochemicals
Substances manufactured from the by-products of petroleum
121
Significance of petrochemicals
manufacture of such compounds has become an important industry
122
Term
Definition
123
Original application of organic chemistry
study of substances of plant or animal origin
124
Modern ability to create organic substances
most of these substances can be synthesized from inorganic materials in the laboratory
125
Additional compounds in organic chemistry
many other similar compounds which do not have any connection with living organisms are also known
126
Modern definition of organic chemistry
chemistry of carbon compounds
127
Compounds excluded from organic chemistry
a few compounds such as the oxides
128
Reasons for grouping carbon compounds in a separate branch of chemistry
large number
129
Main element in organic compounds
carbon
130
Other elements usually present in organic compounds
hydrogen and oxygen
131
Elements sometimes present in organic compounds
nitrogen
132
Reasons for the presence of numerous organic compounds
exceptional ability of carbon atoms to catenate
133
Catenate
combine with one another to form straight chains
134
Term
Definition
135
Flammability of most organic compounds
flammable and burn exothermically in a plentiful supply of air to yield carbon(IV) oxide and water
136
Covalent nature of carbon atoms
form stable covalent bonds with one another
137
Energy of a carbon-carbon single covalent bond
346 kJ mol-1 (high energy indicates a strong bond)
138
Stability of most organic compounds
stable because of the strong carbon-carbon bonds
139
Ionization and electrical conductivity of organic compounds
do not ionize in solution and are non-conductors of electricity (due to covalent nature)
140
Polarity of carbon-hydrogen bonds
non-polar
141
Polarity of most organic compounds
non-polar (unless the compounds consist of very electronegative elements like chlorine or groups like the hydroxyl group)
142
Solubility of most organic compounds in water
insoluble (because most organic compounds are non-polar and cannot form bonds with water molecules)
143
Example of non-polar organic compounds insoluble in water
petrol
144
Condition for organic compound to dissolve in water
contains polar groups
145
Example of organic compound soluble in water
ethanol (molecule contains a hydroxyl group which is polar)
146
Intermolecular forces in non-polar substances
Weak intermolecular forces such as the van der Waals forces
147
Solubility of most organic compounds
dissolve only in non-polar solvents like benzene or ether (because non-polar substances can intermingle easily)
148
Melting and boiling points of organic compounds
generally have lower melting and boiling points than inorganic compounds
149
Reason for low melting and boiling points
these compounds possess relatively weak intermolecular bonds which can be easily broken by heat energy
150
Volatility of many organic compounds
tend to be volatile and boil at temperatures below 300°C (mainly those with low relative molecular masses)
151
Thermal instability of many organic compounds
thermally unstable
152
Commercial importance of thermal instability
sometimes of commercial importance as in the cracking of petroleum
153
Organic compounds that are fuels
wood
154
Reactivity of reactions involving organic compounds
tend to be much slower than the ionic reactions commonly encountered in inorganic chemistry
155
Factors that speed up organic reactions
usually require heating
156
Term
Definition
157
starch to maltose conversion enzyme
diastase.
158
Maltose formula
C12H22O11(aq).
159
Maltose to glucose conversion enzyme
maltase.
160
Glucose formula
C6H12O6(aq).
161
Glucose to ethanol and carbon(IV) oxide conversion enzyme
zymase.
162
Ethanol formula
C2H5OH(aq).
163
Carbon(IV) oxide formula
CO2(g).
164
Term
Definition
165
Industrial manufacture of ethanol raw materials
molasses
166
Enzymes for ethanol production
diastase
167
Term
Definition
168
starch to maltose conversion enzyme
diastase.
169
Maltose to glucose conversion enzyme
maltase.
170
Glucose to ethanol and carbon(IV) oxide conversion enzyme
zymase.
171
Molasses
syrupy liquid remaining after sugar crystallization.
172
Molasses main component
sucrose.
173
Sucrose conversion enzymes
invertase and zymase.
174
Sucrose conversion products
glucose and fructose.
175
Glucose and fructose conversion product
ethanol.
176
Term
Definition
177
starch to maltose conversion enzyme
diastase.
178
Maltose to glucose conversion enzyme
maltase.
179
Glucose to ethanol and carbon(IV) oxide conversion enzyme
zymase.
180
Term
Definition
181
Alkanoic acids
also known as organic or carboxylic acids
182
Aliphatic monocarboxylic acids
contain one carboxyl group per molecule.
183
Aliphatic monocarboxylic acids general molecular formula
$C_{n}H_{2n+1}COOH$ where $n\ge0$
184
Aliphatic monocarboxylic acids other name
fatty acids because some of them are found in natural fats and oils.
185
IUPAC name of each homologue
obtained by changing the -e ending of the corresponding alkane to -oic acid.
186
Dicarboxylic acids
have two carboxyl groups per molecule.
187
Dicarboxylic acids examples
ethanedioic acid (oxalic acid)
188
Tricarboxylic acids
have three carboxyl groups per molecule.
189
Tricarboxylic acids example
2-hydroxypropane-1
190
Two important aromatic carboxylic acids
benzoic acid and 2-hydroxybenzoic acid (salicylic acid).
191
Term
Definition
192
Physical properties of alkanoic acids
The first three members are colourless liquids with sharp
193
Physical properties of alkanoic acids
The next six members are oily liquids with unpleasant odours.
194
Physical properties of alkanoic acids
The higher members are waxy solids which are odourless.
195
Solubility of alkanoic acids in water
The first four acids are soluble in water.
196
Reason for solubility of first four acids in water
They can form hydrogen bonds with water molecules.
197
Solubility of higher members in water
They are insoluble in water.
198
Reason for insolubility of higher members in water
The size of the non-polar hydrocarbon chain increases
199
Melting and boiling points of alkanoic acids
They have relatively high melting and boiling points compared with other organic compounds of similar relative molecular masses.
200
Reason for high melting and boiling points
The molecules are associated by strong intermolecular hydrogen bonds.
201
Term
Definition
202
Chemical properties of alkanoic acids
Alkanoic acids are weak acids.
203
Reason for Alkanoic acids being weak acids
They ionize only slightly in aqueous solutions to give hydrogen ions and alkanoate ions.
204
Strength of alkanoic acids
Their strength decreases as the length of the carbon chain increases.
205
Reaction of alkanoic acids with metals
They react with metals above hydrogen in the reactivity series to liberate hydrogen gas and form alkanoates (salts).
206
Reaction of alkanoic acids with trioxocarbonates(IV) and hydrogentrioxocarbonates(IV)
They react with trioxocarbonates(IV) and hydrogentrioxocarbonates(IV) to liberate carbon(IV) oxide gas and form alkanoates.
207
Reaction of alkanoic acids with alkanols
They react with alkanols in the presence of a few drops of concentrated tetraoxosulphate(VI) acid to form esters and water.
208
Term
Definition
209
Uses of alkanoic acids
Methanoic acid is used in the rubber
210
Uses of alkanoic acids
Ethanoic acid is used as a food preservative and for making ethanoate salts
211
Uses of alkanoic acids
Hexadecanoic acid and octadecanoic acid are used in making soaps and detergents.
212
Term
Definition
213
Esters
are sweet-smelling organic compounds formed by the reaction between alkanoic acids and alkanols in the presence of a few drops of concentrated tetraoxosulphate(VI) acid.
214
Esterification
The reaction is known as esterification.
215
Esters functional group
$-COOR$ or $-COO-$.
216
Esters general molecular formula
$RCOOR'$ where R and R' are alkyl groups.
217
Naming of esters
The name of an ester is derived from the names of the alkanol and alkanoic acid from which it is formed.
218
Naming of esters
The alkyl group (R') from the alkanol comes first
219
Term
Definition
220
Uses of esters
Esters are used as flavouring agents in the food industry and in the manufacture of perfumes because of their sweet
221
Uses of esters
Ethyl ethanoate is used as a solvent for paints
222
Soap
Soap is a sodium or potassium salt of higher fatty acids such as hexadecanoic acid (palmitic acid)
223
Soap preparation
Soap is prepared commercially by heating animal fats or vegetable oils with concentrated sodium hydroxide solution.
224
Saponification
This process is known as saponification.
