org Flashcards
(147 cards)
1
Q
What is the defining characteristic of carbon in organic chemistry?
A
Carbon has four valence electrons which it can share with other atoms to form strong covalent bonds.
2
Q
What are hydrocarbons?
A
Compounds containing only carbon and hydrogen atoms.
3
Q
What is a saturated hydrocarbon?
A
A hydrocarbon in which all carbon atoms are bonded to four other atoms, with all single bonds.
4
Q
What is the general formula for alkanes?
A
CnH2n+2
5
Q
List the names of the first five alkanes.
A
- Methane
- Ethane
- Propane
- Butane
- Pentane
6
Q
What is a homologous series?
A
A family of compounds where each member differs from the previous one by a -CH2- unit.
7
Q
What are alkyl groups?
A
Groups of atoms derived from alkanes that replace one hydrogen atom in the carbon chain.
8
Q
What is the systematic naming process for alkanes?
A
- Identify the longest carbon chain
- Identify all side chains
- Number the carbon atoms for the lowest numbers to alkyl groups
- Use prefixes di- or tri- for multiple alkyl groups
- Name in alphabetical order.
9
Q
What products are typically formed when hydrocarbons combust?
A
Carbon dioxide and water vapour.
10
Q
True or False: Alkenes and alkynes are more reactive than alkanes.
A
True
11
Q
What is benzene’s chemical formula?
A
C6H6
12
Q
What type of reactions does benzene predominantly undergo?
A
Substitution reactions.
13
Q
Define electronegativity.
A
The relative attraction that an atom has for shared electrons in a covalent bond.
14
Q
Fill in the blank: The unequal attraction for shared electrons creates a _______.
A
polar bond
15
Q
What are Van der Waals forces?
A
Weak forces of attraction between molecules due to temporary dipoles.
16
Q
What is hydrogen bonding?
A
A strong dipole-dipole attraction between hydrogen and electronegative atoms like oxygen, nitrogen, or fluorine.
17
Q
How do intermolecular forces affect boiling points?
A
Stronger intermolecular forces result in higher boiling points.
18
Q
What determines the solubility of a molecule?
A
The polarity of the molecule and the solvent.
19
Q
What is a functional group?
A
An atom or group of atoms that determines the chemical properties of an organic compound.
20
Q
True or False: Alkyl halides have lower melting and boiling points than their corresponding alkanes.
A
False
21
Q
What are alkyl halides?
A
Compounds of the form RX, where X = F, Cl, Br, I
Alkyl halides are organic compounds containing a halogen atom.
22
Q
What physical property do alkyl halides have compared to corresponding alkanes?
A
Higher melting and boiling points due to dipole-dipole interactions
This is due to differences in electronegativity.
23
Q
Are most alkyl halides soluble in water?
A
No, most are insoluble in water.
Solubility depends on the length of the carbon chain.
24
Q
How can alkyl halides be prepared?
A
By the reaction of hydrocarbons with halogens or hydrogen halides
Examples include Cl2, Br2, I2, HBr, HCl, HI.
25
What is the general formula for alcohols?
ROH
## Footnote
The 'R' represents an alkyl group.
26
How are alcohols named?
By taking the name of the corresponding alkane and replacing 'e' with 'ol'
## Footnote
The position of the hydroxyl group is numbered if necessary.
27
What are the classifications of alcohols based on the carbon structure?
Primary, Secondary, Tertiary
## Footnote
Primary alcohol has -OH attached to a carbon bonded to one other carbon.
28
What is a primary alcohol?
Hydroxyl group carbon attached to only one other carbon atom.
29
What is a secondary alcohol?
Hydroxyl group carbon attached to two other carbon atoms.
30
What is a tertiary alcohol?
Hydroxyl group carbon attached to three other carbon atoms.
31
What effect does the hydroxyl group have on the boiling point of alcohols?
Alcohols have a higher boiling point than corresponding alkanes due to hydrogen bonding.
32
What happens to the solubility of alcohols as the carbon chain length increases?
Solubility decreases with increasing chain length.
33
What is the pH of alcohols?
Neutral pH.
34
What reaction do alcohols undergo with carboxylic acids?
They form esters.
35
What are phenols?
Alcohols with a hydroxyl group attached to a benzene ring.
36
What are diols and triols?
Compounds with two or three hydroxyl groups attached to carbon chains.
37
What are aldehydes?
Alkanes with a carbonyl group (C=O) on an end carbon.
38
How are aldehydes named?
By taking the name of the corresponding alkane and replacing 'e' with 'al'.
39
What is the solubility of smaller aldehydes in water?
They are soluble due to the polar carbonyl group.
40
What are ketones?
Compounds of the form RCOR’.
41
How are ketones named?
By taking the name of the corresponding alkane and replacing 'e' with 'one'.
42
What is the main characteristic of carboxylic acids?
They contain a carboxyl group (COOH).
43
How are carboxylic acids named?
By replacing 'e' in the corresponding alkane name with 'oic' followed by 'acid'.
44
What is the boiling point of carboxylic acids compared to alcohols?
Higher due to the ability to form hydrogen bonds at two points.
45
What occurs when carboxylic acids react with metals like Na or Mg?
They produce corresponding salts and hydrogen gas.
46
What is the oxidation product of primary alcohols?
Aldehydes, which can further oxidize to carboxylic acids.
47
What is the oxidation product of secondary alcohols?
Ketones.
48
Do tertiary alcohols undergo oxidation?
No, they do not oxidize.
49
What are esters formed from?
The reaction of a carboxylic acid and an alcohol.
50
How are esters named?
From the alkyl chain of the alcohol and the acid name with 'oic' replaced by 'oate'.
51
What are amines?
Compounds containing an amine group (RNH2).
52
How are amines named?
By dropping the final 'e' of the parent hydrocarbon and adding 'amine'.
53
What is the pH of aqueous solutions of amines?
Weakly basic.
54
What are amides?
Compounds containing a carbonyl group attached to a nitrogen atom (RCONH2).
55
How are amides named?
By dropping 'oic acid' from the parent carboxylic acid name and adding 'amide'.
56
What is the structure of methanamide?
HCONH2
## Footnote
Methanamide is the simplest amide.
57
What is the structure of ethanamide?
CH3CONH2
## Footnote
Ethanamide is also known as acetamide.
58
What is the pH of aqueous solutions of amides?
Neutral
## Footnote
Aqueous solutions of amides do not exhibit acidic or basic properties.
59
How are amides formed?
By reacting ammonia with a carboxylic acid
## Footnote
This process results in the formation of an amide and water.
60
What do amides undergo upon hydrolysis?
Yield carboxylic acids plus ammonia
## Footnote
Hydrolysis can occur in dilute acid or aqueous base.
61
What is an amino acid composed of?
A basic amino group (―NH2), an acidic carboxyl group (―COOH), and an organic R group
## Footnote
The R group is unique to each amino acid.
62
What is the highest priority functional group in naming compounds with more than one functional group?
Carboxylic acid
## Footnote
The priority scale for functional groups follows: Carboxylic acid > Ester > Aldehyde > Ketone > Alcohol > Amine > Alkyne/alkene > alkane.
63
What is the general method for naming compounds derived from benzene?
Substitution reactions
## Footnote
Benzene typically undergoes substitution rather than addition reactions.
64
What is chlorobenzene?
A benzene ring with a chlorine atom substituted for one hydrogen
## Footnote
Chlorobenzene is used as a solvent and in the synthesis of other chemicals.
65
What are the two main types of polymers?
Addition polymers and condensation polymers
## Footnote
Addition polymers are formed from monomers with double bonds, while condensation polymers are formed from bifunctional monomers.
66
What is the process of forming polymers from monomers called?
Polymerisation
## Footnote
Polymerisation involves covalent bond formation between monomer molecules.
67
What is addition polymerisation?
A reaction process leading to the formation of thermoplastic polymers
## Footnote
It typically involves unsaturated hydrocarbons with carbon/carbon double bonds.
68
What is an example of a common addition polymer?
Polyethylene
## Footnote
Polyethylene is derived from the monomer ethene.
69
What characterizes condensation polymers?
Form chains through bifunctional monomers with two functional groups
## Footnote
The process often involves the elimination of small molecules like water.
70
What is a polyester?
A polymer formed from an alcohol with two OH groups and a carboxylic acid with two COOH groups
## Footnote
The formation involves esterification.
71
What is mass spectrometry used for in organic chemistry?
To determine the molecular mass and assist in identifying functional groups
## Footnote
It involves ionising an organic compound and analyzing it using an electromagnetic field.
72
What does the base peak in mass spectra represent?
The most stable fragment with 100% relative abundance
## Footnote
The base peak helps identify some structure of the organic molecule.
73
What is IR spectroscopy used for?
To identify specific functional groups in molecules
## Footnote
Different functional groups absorb IR radiation at characteristic frequencies.
74
Fill in the blank: The chemical process of linking monomers to produce a polymer chain is called _______.
Polymerisation
75
True or False: Most polymers are good conductors of electricity.
False
## Footnote
Most polymers are non-conductors of electricity.
76
What is the m/z value for 79Br?
m/z = 79
77
What are the m/z values for the M+ peaks of 79Br and 81Br?
m/z = 122 for 79Br and m/z = 124 for 81Br
78
What does IR spectroscopy utilize?
The fact that molecules absorb specific IR frequencies characteristic of their structure
79
What functional groups are identified using IR spectra in Chemistry 4?
* Hydroxyl groups, –OH
* Carbonyl groups, C=O
80
What is the wavenumber range for C–H bonds often seen near O–H?
2850 – 3300 cm-1
81
What is the IR absorption characteristic of alcohols?
–OH stretch only
82
What is the IR absorption characteristic of aldehydes, ketones, and esters?
C=O only
83
What is the IR absorption characteristic of carboxylic acids?
BOTH the –OH (broader) and the C=O stretch
84
What is X-Ray crystallography used for?
To determine the structures of crystals
85
What happens when propanal reacts with Na?
Produces a product that can be oxidized
86
What is the molar mass of compound A if it has the formula C3H8O?
60 g mol-1
87
What is produced when compound B reacts with ethanol?
A compound C with a strong smell
88
What is the empirical formula for compounds A and B if they consist of 40.0% carbon, 6.7% hydrogen, and the rest oxygen?
C2H4O
89
What is the systematic name for a compound containing 4 carbon atoms with a peak at 1700 cm-1?
A carboxylic acid
90
What type of reaction occurs when methanamide is heated in an aqueous base?
Hydrolysis reaction
91
What is the base peak at m/z = 30 for spectrum B?
A specific fragment of the compound
92
What is the mass spectrum peak for propanone at M+?
M+ peak is identified at m/z = 58
93
Which compound can be produced by oxidizing a secondary alcohol?
A ketone
94
What is the expected difference in spectra between a carboxylic acid and a chloroalkane?
Carboxylic acid shows a broad –OH peak
95
What is the reaction of ethanol with acidified KMnO4?
Oxidation to produce an acid
96
What is produced when butan-2-ol reacts with acidified KMnO4?
A ketone
97
What are the structural formulas for ethanamine and pentan-2-amine?
Ethanamine: CH3CH2NH2; Pentan-2-amine: CH3CH(NH2)CH2CH2CH3
98
What is the molecular mass of the compound with empirical formula C2H4O?
Molecular mass is determined from the mass spectrum
99
What evidence supports the identification of nitrogen dioxide in mass spectra?
The specific peak patterns and fragmentations
100
What does the base peak at m/z = 43 in propanone indicate?
A stable fragment due to the structure of propanone
101
What method can verify the purity of ethyl propanoate?
Gas chromatography to check for reactant traces
102
What reactions can be used to produce butan-2-amine?
* From butan-1-ol and ammonia
* From 2-chlorobutane and ammonia
103
What is the expected product when a tertiary alcohol is oxidized?
No reaction occurs
104
What is the reaction of propan-1-ol with K2Cr2O7?
Oxidation to produce propanoic acid
105
What gas is involved in the equation mentioned?
H2
106
What salt is used in the reaction?
Magnesium propanate
107
What types of structures can A be?
Isomer of butene (but-2-ene or 2-methylpropene), cyclobutane, methylcyclopropane
108
Which isomer of butene is ruled out based on the reaction outcome?
But-2-ene
109
What products does but-1-ene produce?
1-chlorobutane and 2-chlorobutane
110
What products does methylpropene produce?
1-chloro-2-methylpropane and 2-chloro-2-methylpropane
111
What type of alcohol does part of the reaction indicate can be oxidized to an aldehyde?
Primary alcohol
112
What type of alcohol does part of the reaction indicate can be oxidized to a non-acidic ketone?
Secondary alcohol
113
Identify the structure of A.
But-1-ene
114
What is the product B?
1-chlorobutane
115
What is the product B'?
2-chlorobutane
116
What is the structure of C?
Butan-1-ol
117
What is the structure of D?
Butanal
118
What is the structure of E?
Butanoic acid
119
What is the structure of C'?
Butan-2-ol
120
What is the structure of F?
Butan-2-one
121
What gas is produced when the acid reacts with Mg?
H2
122
What gas is produced when the acid reacts with Na2CO3?
CO2
123
What happens when propanal reacts with acidified potassium permanganate solution?
What happens when propanal reacts with acidified potassium permanganate solution?
124
What does propan-1-ol reduce to when reacted with acidified potassium permanganate solution?
Propanoic acid
125
What does propan-2-ol reduce to when reacted with acidified potassium permanganate solution?
Propanone
126
What indicates that propan-1-ol reduces twice the amount of permanganate solution?
It undergoes two reactions
127
What is observed when cyclohexane reacts with bromine solution?
Decolours immediately
128
How does butan-2-ol behave when reacted with acidified permanganate solution?
Decolours
129
What is the behavior of methylpropan-2-ol when reacted with acidified permanganate solution?
No reaction
130
What happens when ethanol is heated gently in a water bath?
Vaporises readily
131
What is the molecular weight of the compound with an M peak at 86?
86
132
What is the structure corresponding to the M peak at 86?
CH3CH2CH2CH2
133
What is the molecular weight of the compound with an M peak at 58?
58
134
What is the structure corresponding to the M peak at 58?
CH3C=O
135
Can A be NO2 based on the peak analysis?
False
136
What are the two ends of ethanol in terms of polarity?
Non-polar end (carbon chain) and polar end (alcohol group)
137
What is the molecular formula of A if it is a primary alcohol?
CH2O
138
What must B be if A is a primary alcohol?
Ethanoic acid
139
What is the reaction of mixing propanoic acid with ethanol?
Produces an ester
140
What is produced when sodium metal reacts with carboxylic acid and alcohol?
Hydrogen gas (H2)
141
What compound does not react with sodium metal?
Chloroalkane
142
What is the IR peak range for alcohol?
3650 – 3200
143
What is the IR peak range for carboxylic acid?
1780 – 1650 and 3300 – 2500
144
What is the formula for an ester?
CnH2nO2
145
What must the neutral compound (A) be if it has 1 carbon atom?
Methanol
146
What does the oxidation of a secondary alcohol produce?
Ketone
147
What is the structure of C if it is methyl butanoate?
Methyl butanoate
