Unit 2 Flashcards
(194 cards)
1
Q
What are saturated compounds?
A
Saturated compounds contain only single carbon-carbon bonds.
2
Q
What are unsaturated compounds?
A
Unsaturated compounds contain at least one carbon-carbon double bond.
3
Q
What type of bond is present in saturated compounds?
A
Saturated compounds have Only single carbon-carbon bond.
4
Q
What type of bond must unsaturated compounds contain?
A
Unsaturated compounds must contain at least one carbon–carbon double bond.
5
Q
What is an addition reaction?
A
An addition reaction is a reaction in which two molecules combine to form a single molecule.
5
Q
Why can compounds containing carbon – carbon double bonds take part in addition reactions?
A
The double bond allows unsaturated compounds to react with other molecules, Combining them into one.
6
Q
How can bromine solution be used to distinguish between saturated and unsaturated compounds?
A
Bromine solution quickly decolourises when mixed with unsaturated compounds but remain coloured with Saturated compounds.
7
Q
What happens when an unsaturated compound is mixed with bromine solution?
A
The bromine solution is quickly decolourised.
8
Q
What are the two ways in which the structure of the molecule can be represented?
A
Molecules can be represented using a full structural formula or a shortened structural formula.
9
Q
What are isomers?
A
Isomers are compounds with the same molecular formula but different structural formulae.
10
Q
What do isomers have in common?
A
Isomers have the same molecular formula.
11
Q
How do isomers differ from one another?
A
Isomers differ in their structural formulae.
12
Q
Can isomers belong to different homologous series?
A
Yes, isomers may belong to different homologous series.
13
Q
How do isomers typically differ in terms of physical properties?
A
Isomers usually have different physical properties, such as boiling points and solubility?
14
Q
What information is needed to draw an isomer of a compound?
A
The molecular formula of the compound is needed to draw an isomer.
15
Q
What factors affect the solubility, boiling points, and volatility of a compound?
A
Factors include the presence of O-H or N-H bonds, the spatial arrangement of polar covalent bonds, molecular size, and the polarities of solute and solvent.
15
Q
How does the presence of O-H or N-H bonds affect solubility, boiling point, and volatility?
A
The presence of O-H or N-H bonds implies hydrogen bonding, which increases solubility, boiling point, and decreases volatility.
16
Q
What is the effect of molecular size on the strength of London dispersion forces?
A
Larger molecules have more electrons, resulting in stronger London dispersion forces.
17
Q
How does the spatial arrangement of polar covalent bonds affect a molecules dipole?
A
The spatial arrangement an result in the molecule having a permanent dipole, making it polar.
18
Q
How does the polarity of a solute and solvent affect solubility?
A
Polar solutes dissolve in polar solvents, and non-polar solutes dissolve in non-polar solvents.
19
Q
What type of solvents are polar or ionic compounds typically soluble in?
A
Polar or ionic compounds are typically soluble in polar solvents.
20
Q
What type of solvents are non-polar compounds typically soluble in?
A
Non-polar compounds are typically soluble in non-polar solvents.
21
Q
What is the relationship between solubility, boiling point, and volatility with intermolecular forces?
A
Stronger intermolecular forces increase solubility and boiling points bus decrease volatility.
22
Q
How do the type and strength of intermolecular forces explain differences in boiling points?
A
Compounds with strongest intermolecular forces, such as hydrogen bonding, have higher boiling points.
23
Why are polar compounds generally more soluble in polar solvents?
Polar compounds can form intermolecular interactions with polar solvents, enhancing solubility.
24
Why are non-polar compounds generally more volatile than polar compounds?
Non-polar compounds have weaker intermolecular forces (e.g. London dispersion forces), making them easier to evaporate.
25
What is the functional group present in alcohols?
The hydroxyl group (-OH) is the functional group present in alcohols.
26
What is the general formula of the hydroxyl functional group?
The hydroxyl group is represented as -OH.
27
What types of alcohols can be named systematically?
Straight-chain and branched alcohols with up to eight carbon atoms in their longest chain can be named systematically.
28
How is the position of the hydroxyl group indicated in the name of an alcohol?
The position of the hydroxyl group is indicated by a number placed before the name, showing the carbon atom to which the hydroxyl group is attached.
29
How many carbon atoms can the longest chain of a systematically named alcohol have?
The longest chain can have up to eight carbon atoms.
30
What are the two types of formulae that can be derived from the systematic name of an alcohol?
The molecular formula and the structural formula can be derived from the systematic name.
31
What is the difference between a straight-chain alcohol and a branched alcohol?
A straight-chain alcohol has all carbon atoms in a continuous chain, while a branched alcohol has a side chain attached to the main chain.
32
What are the three classifications of alcohols?
Alcohols are classified as primary, secondary, and tertiary.
33
What is a diol?
A diol is an alcohol containing two hydroxyl (-OH) groups.
34
What is a triol?
A triol is an alcohol containing three (-OH) groups.
35
Why are alcohols polar molecules?
Alcohols are polar because the hydroxyl group (-OH) creates a significant difference in electronegativity between oxygen and hydrogen.
36
What type of intermolecular force arises due to the hydroxyl group in alcohols?
Hydrogen bonding arises due to the hydroxyl group.
37
What properties of alcohols can be explained by hydrogen bonding?
Hydrogen bonding explains the boiling points, melting points, viscosity, and solubility/miscibility of alcohols in water.
37
How does the hydroxyl group affect the solubility of alcohols in water?
The hydroxyl group allows alcohols to form hydrogen bonds with water, increasing their solubility.
38
What effect does hydrogen bonding have one the boiling points of alcohols?
Hydrogen bonding increases the boiling points of alcohols compared to similar molecule’s without hydroxyl groups.
39
Why do alcohols tend to have higher melting points compared to similar molecules without hydroxyl groups?
Alcohols have higher melting points because hydrogen bonding requires more energy to break.
40
How does hydrogen bonding affect the viscosity of alcohols?
Hydrogen bonding increases the viscosity of alcohols by creating stronger intermolecular attractions.
41
What determines the miscibility of alcohols in water?
The miscibility of alcohols in water is determined by the hydroxyl groups ability to form hydrogen bonds with water molecules.
42
What is the functional group present in carboxylic acids?
The Carboxyl group is the functional group present in carboxylic acids.
42
How is the Carboxyl functional group represented?
The Carboxyl group is represented as -COOH.
43
What types of carboxylic acids can be names systematically?
Straight-chain and branched-chain carboxylic acids can be named systematically.
44
What is the maximum number of carbon atoms allowed in the longest chain of carboxylic acid for systematic naming?
The longest chain can contain no more than eight carbon atoms.
45
What two types of formulae can be derived from the systematic name of a carboxylic acid?
The molecular formula and the structural formula can be derived from the systematic name.
46
What is the difference between a straight-chain and a branched-chain carboxylic acids?
A straight-chain carboxylic acid has all its carbon atoms in a continuous chain, while a branched-chain carboxylic acid has side chains attached to the main chain.
47
What products are formed when a carboxylic acid reacts with a metal oxide?
The products are salt and water.
48
What products are formed when a carboxylic acid reacts with a metal hydroxide?
The products are salt and water.
49
What products are formed when a carboxylic acid reacts with a metal carbonate?
The products are salt, water, and carbon dioxide.
50
What additional product is formed in the reaction between a carboxylic acid and a metal carbonate that is not formed in reactions with metal oxides or hydroxides?
Carbon dioxide is the additional product.
51
What determines the name of the salt produced in the reaction involving a carboxylic acid.
The name of the salt depends on the carboxylic acid and the base used in the reaction.
52
How does the choice of acid and base affect the name of the salt?
The acid provides the first part of the salt name (e.g ethanoate from ethanoic acid) while the base provides the cation (e.g. sodium from sodium hydroxide )
53
What functional group is present in ester?
The ester link is present in ester.
54
How is the ester link represented?
The ester link is represented as -COO-.
55
What information is required to name an ester?
The names of its parent alcohol and carboxylic acid, of the structural formula of the ester.
56
How many carbon atoms can the parent alcohol and carboxylic acid contain for naming esters systematically?
Each can contain no more than eight carbon atoms in their longest chain.
57
What two types of formulae can be written for esters given their systematic name?
The molecular formula and the structural formula.
58
What is the relationship between an ester and its parent alcohol and carboxylic acid?
An ester is formed from the condensation of a hydroxyl group (from the alcohol) and a carboxyl group (from the carboxylic acid).
59
What are two common uses of esters?
Esters are used as flavourings and fragrances.
60
Why are esters commonly used as flavourings and fragrances?
Many esters have pleasant, fruity smells.
61
Why are esters effective solvents for non-polar compounds?
Esters dissolve in non-polar compounds that do not dissolve in water.
62
What type of reaction forms esters?
Esters are formed through condensation reactions.
63
What happens in condensation reactions?
Two molecules join together with the elimination of a small molecule.
64
What two functional groups react to form an ester?
A hydroxyl group (-OH) and a carboxyl group (-COOH).
65
What small molecule is eliminated during the formation of an ester?
Water is eliminated.
66
What is hydrolysis?
Hydrolysis is a reaction where a molecule reacts with water to break down into smaller molecules.
67
What are the products of hydrolysing an ester?
An alcohol and a carboxylic acid.
68
How can the name of an ester help determine the products of hydrolysis?
The name of the ester indicates the parent alcohol and carboxylic acid that are formed upon hydrolysis.
69
What information is required to write molecular and structural formulae for the products of ester hydrolysis?
The systematic name of structural formula of the ester.
70
What are edible fats and oils chemically?
Edible fats and oils are esters.
71
What reactants combine to form edible fats and oils?
Glycerol (propane-1,2,3-triol) and three carboxylic acid molecules (fatty acids).
72
What are fatty acids, and what types can they be?
Fatty acids are long chain carboxylic acids that can be saturated or unsaturated.
73
Why do edible oils have lower melting points than fats?
The double bonds in the fatty acid chains of oils prevent the molecules from packing closely together, weakening van der Waals forces.
74
What prevents oil molecules from packing closely together?
The presence of double bonds in the fatty acid chains.
75
How does the degree of unsaturation affect the melting point of oils?
A higher degree of unsaturation (More double bonds) Lowers the melting point.
76
What happens when bromine solution is added to an unsaturated compound?
The bromine solution is quickly decolorized as bromine molecules add across the carbon-carbon double bonds.
77
What does the amount of bromine solution decolourised indicate about an oil or fat?
It indicates the number of double bonds present; The greater the decolourisation, The more double bonds are present.
78
What are the two key biological roles of fats and oils?
Fats and oils are a concentrated source of energy and essential for the transport and storage of fat-soluble vitamins.
79
Why are fats and oils essential for the body?
They provide energy and are necessary for the storage and transport of vitamins that dissolve in fat.
80
How are soaps produced?
Soaps are produced by the alkaline hydrolysis of edible fats and oils.
80
What are the products of the alkaline hydrolysis of fats and oils?
Three fatty acid molecules and one glycerol molecule are produced.
81
What is the role of alkali in soap production?
The alkali neutralises the fatty acids, forming water-soluble, ionic salts called soaps.
81
What type of compounds are soaps?
Soaps are ionic salts of fatty acids.
82
What are two key parts of a soap molecule?
A soap molecule has a long non-polar hydrophobic tail and an ionic hydrophilic head.
83
What is the role of the hydrophobic tail of a soap molecule?
The hydrophobic tail dissolves in oil or grease.
84
What is the role of the hydrophilic head of a soap molecule?
The hydrophilic head is water soluble and interacts with water molecules.
84
How do soap molecules interact with oil or grease?
The hydrophobic tails dissolve in the oil or grease, While the hydrophilic heads remain in the surrounding water.
85
What happens to the hydrophilic heads of soap molecules in water?
The hydrophilic heads remain in the surrounding water and form negatively charged structures.
86
What processes form ball like structures during soap cleaning?
Agitation causes the soap molecules to form ball like structures.
87
Why do the ball like structures repel each other in water?
The negatively charged hydrophilic heads on the surface of the structure repel each other, Keeping the oil or grease suspended in water.
88
What is a hard water?
Hard water contains high levels of dissolved metal ions.
88
What happens when soap is used in hard water?
Soap reacts with metal ions forming scum an insoluble precipitate.
89
What is scum and why does it form?
Scum is an insoluble precipitate that forms when soap reacts with the metal ions in hard water.
90
What are soapless detergents?
Soapless detergents are substances with non-polar hydrophobic tails and ionic hydrophilic heads, similar to soap.
90
How do soapless detergents remove oil and grease?
They remove oil and grease in the same way as soaps, with their hydrophobic tails dissolving in the oil and their hydrophilic heads interacting with water.
91
Why are soapless detergents useful in hard water?
Soapless detergents do not form scum with hard water.
92
What is an emulsifier ?
An emulsifier prevents non-polar and polar liquids from separating into layers.
93
What is an emulsion?
An emulsion is a mixture where small droplets of one liquid are dispersed in another liquid.
94
How are emulsifiers used in food production?
Emulsifiers are used to create stable mixtures of oil and water in food products.
95
How are emulsifiers made for use in food?
They are made by reacting edible oils with glycerol.
96
What are the two functional parts of an emulsifier molecule?
Emulsifier molecule have hydrophilic hydroxyl groups and hydrophobic fatty acid chains.
97
What is the role of hydrophilic part of an emulsifier molecule?
The hydrophilic part dissolves in water.
98
What is the role of the hydrophobic part of an emulsifier molecule?
The hydrophobic part dissolves In oil.
99
How does an emulsifier help form a stable emulsion?
The hydrophobic part dissolves in oil, and they hydrophilic part dissolves in water, preventing the two liquids from separating into layers.
100
How are soapless detergents similar to soaps?
Both have hydrophobic tails and hydrophilic heads and remove oil or grease in the same way.
101
How do soapless detergents differ from soaps in their interaction with hard water?
Soapless detergents do not form scum in hard water, unlike soaps.
102
What is the difference between soap and an emulsifier in terms of their function?
Soap removes oil and grease by forming ball-like structures, while an emulsifier prevents polar and non-polar liquids from separating into layers.
103
What are the major structural materials of animal tissue?
Proteins are the major structural materials of animal tissue.
104
What role do proteins play in life processes?
Proteins are involved in the maintenance and regulation of life processes.
105
What are enzymes, at what is their role?
Enzymes are proteins that act as biological catalysts.
106
What are the building blocks of proteins?
Amino acids are the building blocks of proteins.
107
What two functional groups are present in all amino acids?
Amino acids contain an amino group (-NH2) and a carboxyl group (-COOH).
108
How are proteins formed from amino acids?
Proteins are formed by linking many amino acid molecules together through condensation reactions.
109
What happens during a condensation reaction between amino acids?
The amino group of one amino acid reacts with the carboxyl group of another, forming a peptide link (-CONH-) and eliminating a water molecule.
110
What is another name for the peptide link in proteins?
The peptide link is also known as an amide link.
110
How are proteins with different roles in the body formed?
Proteins with different roles are formed by linking amino acids in varying sequences.
111
What are essential amino acids?
Essential amino acids are amino acids that the body cannot synthesise and must be obtained from the diet.
112
What happens to proteins during digestion?
Proteins are hydrolysed by enzymes into amino acids during digestion.
113
What is the structural formula of amino acids obtained from protein hydrolysis based on?
It is based on the structure of the section of protein that was hydrolysed.
114
How can the structural formula of a protein section be determined?
It can be drawn using the structural formulae of the amino acids from which it is formed.
115
What shapes can protein molecules form?
Protein molecules can form spirals, sheets, or other complex shapes.
116
What holds protein chains in their specific shapes?
Intermolecular binding between the side chains of constituent amino acids holds the chains in their specific shapes.
117
What happens to proteins when they are heated?
Intermolecular bonds are broken, allowing the proteins to change shape (denature).
118
How does the denaturation of proteins affect food?
Denaturation changes the texture of foods when they are cooked.
119
What causes proteins in food to change texture during cooking?
The breaking of intermolecular bonds and denaturation of proteins cause the texture of foods to change.
120
Why is it necessary to include essential amino acids in the diet?
The body cannot synthesise essential amino acids, so they must be obtained from food.
121
What type of reaction is responsible for forming peptide links in proteins?
Condensation reactions form peptide links in proteins.
122
What type of reaction breaks proteins down into amino acids?
Hydrolysis reactions break proteins down into amino acids.
123
What is oxidation in carbon compounds?
Oxidation is an increase in the oxygen to hydrogen ratio.
124
What is reduction in carbon compounds?
Reduction is a decrease in the oxygen to hydrogen ratio.
125
Which oxidising agents can be used to oxidise alcohols?
Hot copper(II) oxide and acidified dichromate(VI) solutions.
126
What happens to copper(II) oxide during oxidation reactions with alcohols?
It forms a brown solid.
127
What color change is observed when acidified dichromate(VI) oxidises alcohols?
It turns from orange to green.
128
What are the oxidation products of primary alcohols?
Primary alcohols are oxidised to aldehydes and then to carboxylic acids.
129
What is the oxidation product of secondary alcohols?
Secondary alcohols are oxidised to ketones.
130
Why can’t tertiary alcohols be oxidised using hot copper(II) oxide or acidified dichromate(VI)?
Tertiary alcohols do not have a hydrogen atom attached to the carbon bonded to the hydroxyl group.
131
What functional group is present in aldehydes and ketones?
The Carbonyl group (C=O)
131
What is the difference between aldehydes and ketones?
Aldehydes can be oxidised to carboxylic acids, while ketones cannot.
132
what are some uses of aldehydes?
Many flavour and aroma molecules are aldehydes.
133
What oxidising agents can differentiate between aldehydes and ketones?
- Blue fehlings solution forms a brick-red precipitate with aldehydes.
- Clear, colorless Tollens reagent forms a silver mirror with aldehydes.
- Orange acidified dichromate solution turns green with aldehydes.
134
What is the systematic naming limit for aldehydes and ketones?
They can be named systematically if they contain no more than eight carbons in their longest chain.
135
What causes the oxidation of food?
Oxygen from the air.
136
What affect does the oxidation of edible oils have on food?
It gives food a rancid flavour.
137
What are antioxidants?
Antioxidants are molecules that prevent unwanted oxidation reactions by being easily oxidised themselves.
138
How can antioxidants be identified in redox equations?
They are the substances being oxidised in the reaction.
139
Why are antioxidants added to food?
To protect food by being oxidised in place of the compounds in the food.
140
What observable change occurs when fehlings solution is added to an aldehyde?
A brick-red precipitate forms.
141
What observable change woodcuts when tollens reagent is added to an aldehyde?
A silver mirror forms.
142
What observable change occurs when acidified dichromate reacts with an aldehyde?
The solution turns from orange to green.
143
Why can’t ketones produce the same changed with oxidising agents as aldehydes?
Ketones cannot be further oxidised under normal conditions.
144
What happens to copper(II) oxide during its reaction with alcohols?
It changes from black to a brown solid.
145
What are essential oils?
Essential oils are concentrated extracts of the volatile, non-water soluble aroma compounds from plants.
146
What compounds are found in essential oils?
Essential oils are mixtures of many different compounds, including terpenes.
147
Why are essential oils widely used?
They are widely used for their pleasant aromas and functional properties, such as in perfumes, cosmetic products, cleaning products, and as flavourings in foods.
148
In which products can essential oils be found?
Essential oils can be found in perfumes, cosmetic products, cleaning products, and in food flavourings.
149
What are terpenes?
Terpenes are unsaturated compounds formed by joining together isoprene units.
150
What is the molecular structure of isoprene?
The molecular structure of isoprene is 2-methylbuta-1,3-diene.
151
How are terpenes formed?
Terpenes are formed by the chemicals joining of isoprene units.
152
What type of compounds are terpenes?
Terpenes are unsaturated compounds that contribute to the distinctive aromas of essential oils.
153
Why are terpenes important in essential oils?
Terpenes are key components in essential oils and contribute to their characteristic aromas and biological properties.
154
What role do terpenes play in the aromas of spices?
Terpenes can be oxidised from within plants to produce the compounds responsible for the distinctive aromas of spices.
155
What is the chemical name of isoprene
The chemical name of isoprene is 2-methylbuta-1,2-diene.
156
How can an isoprene unit be identified within a terpene molecule?
An isoprene unit can be identified by locating a repeating 5-carbon structure within the molecule.
157
What is the relationship between terpenes and isoprene units?
Terpenes are formed by the chemical joining of multiple isoprene units.
158
How can the number of isoprene units in a terpene molecule be determined?
The number of isoprene units can be determined by counting the repeating 5-carbon structures in the terpene molecule.
159
What is the structure of an isoprene unit in a structural formula?
The structure of an isoprene unit includes a chain of five carbon atoms with two double bonds.
160
How are terpenes oxidised in plants?
Terpenes are oxidised through natural chemical reactions within plants.
161
What role do oxidised terpenes play in plants?
Oxidised terpenes contribute to the production of distinct aroma compounds in plants.
162
Which compounds are responsible for the distinctive aromas of spices?
Oxidised terpenes are responsible for the distinctive aromas of spices.
163
What happens when terpenes undergo oxidation?
Oxidation alters the chemical structure of terpenes, resulting in the formation of new aroma compounds.
164
How can a terpene-based molecule be analysed to identify isoprene units?
By exams in the structural formula for repeating 5-carbon units with a double bond arrangement.
165
What types of bonds indicate the presence of terpenes in a structural formula?
The presence of double bonds and repeating 5-carbon units indicates terpenes.
166
Why are terpenes described as unsaturated compounds?
Terpenes are described as unsaturated because they contain carbon-carbon double bonds.
167
What type of radiation is UV light and where is it found?
Ultraviolet(UV) radiation is a high-energy form of light found in sunlight.
168
How can UV radiation affect human skin?
It can cause sunburn and accelerate skin ageing.
169
Why are sun-block products Important.
They prevent UV light from reaching the skin, protecting it from damage.
170
What happens to molecules when UV light breaks their bonds?
Free radicals are formed.
171
What is a free radical?
A free radical is an atom or molecule with unpaired electrons, making it highly reactive.
172
Why are free radicals highly reactive?
Because they have unpaired electrons.
172
What are the three steps involved in a free radical chain reaction?
Initiation, propagation, and termination.
172
Describe what happens during the initiation step of a free radical chain reaction?
UV light breaks a bond, forming free radicals.
173
What occurs in the propagation step of a chain reaction?
Free radicals react with stable molecules to form new radicals, continuing the chain.
174
How does the termination step of a chain reaction stop the process?
Two free radicals combine to form a stable molecule, ending the reaction.
174
How can you identify an initiation step in a reaction involving free radicals?
It involves UV light breaking a molecule to form free radicals.
175
What features help you recognise a propagation step?
A free radical reacts to form a new free radical and a stable product.
175
How do you know a reaction step is a termination step?
Two free radicals react to form a stable product with no radicals.
176
What is a free radical scavenger?
A molecule that reacts with free radicals to form stable molecules and stop chan reactions.
177
How do free radical scavengers help prevent chain reactions?
They neutralise free radicals, preventing them from reacting further.
178
Name three types of products where free radical scavengers are commonly added.
Cosmetics, food products, and plastics.
179
Why are free radical scavengers important in cosmetics and food products?
They help prevent oxidative damage and spoilage by stopping chain reactions.
