Organic Chemistry Term 3 Flashcards
(75 cards)
1
Q
Naming 7.1
Alkanes
A
Single carbon bonds
2
Q
Naming 7.1
Alkenes
A
At least one double carbon bond
3
Q
Naming 7.1
Alkynes
A
At least one triple carbon bond
4
Q
Naming 7.1
Structural isomers
A
Contain the same number of atoms of the same element but different structure.
5
Q
Naming 7.1
Number of Carbons
A
Meth 1
Eth 2
Prop 3
But 4
Pent 5
Hex 6
Hept 7
Oct 8
6
Q
Naming 7.1
Nomencalure of Organic compounds
A
7
Q
Naming 7.1
Unsaturated hydrocarbons
A
hydrocarbons that contain at least one double or triple bond between carbon atoms. This means they do not have the maximum number of hydrogen atoms bonded to the carbon skeleton.
8
Q
Naming 7.1
What is the Benzene ring
A
9
Q
Naming 7.1
Different isomers; Chain isomers
A
Changes in the branching of the molecule
10
Q
Naming 7.1
Different isomers: Position isomers
A
The functional group (Br, OH) is attached to a different area
11
Q
Naming 7.1
Different types of isomers: Functional group isomers
A
Different functional groups.
12
Q
Hydrocarbons 7.2
Orbital hybidisation
A
pi= pathetic bonds
sigma= strong bonds
13
Q
Hydrocarbons 7.2
Are all hydrocarbons are nonpolar
Temperature, bloiling point and density
A
yes they are. All have low boiling points, insoluble in water and have a lower density that water. However there are some small differences.
Alkene/Alkane; only have disersion forces
Alcohole; Dipole Dipole hydrogen bonds
Carboxic acid: dipole Dipole hydrogen bonds
14
Q
Hydrocarbons 7.2
What are some chemical properties of hydrocarbons
A
- The combust and are exothermic
Hydrocarbons undergo complete combustion withg hydrogen to for carbon dioxide and water
If oxygen is depleted in combustion CO or unburned C is produced.
15
Q
Hydrocarbons 7.2
How does the hydrogenation of alkynes work
A
Alkynes can turn into aklenes. It can go faster with a nickel catalyst and at room temperature
16
Q
Hydrocarbons 7.2
What are some saftey protocols for organic compounds
A
- Organic chemicals may be volatile( vaporise easily)
- Often flammable
- Irritate skin and eyes
- Must use saftey glasses
17
Q
Hydrocarbons 7.2
What are some everyday uses of hydrocarbons
A
- Natural gas
- LPG (BBQ)
- Petrol and diesel
- Kerosine for jet/aircraft
- Plastic
18
Q
Products of Reactions 7.3
Can you picture the reaction between ethene and Bromine
A
Bromine switches out with H. However this can only happen with a double bond ethene since single bonds do not react.
19
Q
Products of Reactions 7.3
What is hydrogenation
A
The adding of hydrogen
20
Q
Products of reactions 7.3
What us the balance theory
A
That all reactions what to have symmetrical structures as they ahve lower energy, are the most commmon and can defect better from acids and bases.
21
Q
products of reactions 7.3
What does ethene react with oxygen do
A
it produces epoxyethene
Ethene (C₂H₄) + ½O₂ ——(Ag catalyst, heat)——→ Epoxythane (C₂H₄O)
epoxyethane (ethylene oxide) can be converted into an alcohol. Specifically, when it reacts with water in the presence of dilute sulfuric acid
22
Q
Products of reactions 7.3
Ox/Red Balancing Steps
A
- Balance main element
- Balance oxygen with water
- Balance H with H ions
Balance charge with electrons
23
Q
Products of reactions 7.3
What happens when you add hydrogen ions to alkyne
A
alkyne(triple bonds)
add H
Alkene(double bonds)
add H
Ankane (single bonds)
24
Q
Products of reactions 7.3
How do substidution reactions of alkanes with halogens work
A
With the use of a UV light with an above room temperature
25
# Products of reactions 7.3
What happens in hydrogenation with alkenes
Using Nickel as a catalyst and at 150 degrees celcius hydrogenation can happen. Produces an alkane
E.g. But-1-ene + hydrogen
26
# Products of reactions 7.3
What happens in a hydrogen halide reaction with an alkene
In a hydrogen halide (HX) reaction, an alkene reacts with a hydrogen halide (like HCl, HBr, or HI) to form a haloalkane (alkyl halide). This is an example of an electrophilic addition reaction. This can be done at room temperature.
E.g.
Ethene (CH₂=CH₂) + HBr → Bromoethane (CH₃–CH₂Br)
27
# Products of reactions 7.3
What happens in halogenation
Can be done at room temp. alogen molecule (like Cl₂ or Br₂) reacts with an alkene or alkyne, resulting in the addition of halogen atoms across a double or triple bond.
E.g. Ethene (CH₂=CH₂) + Br₂ → 1,2-dibromoethane (CH₂Br–CH₂Br)
28
# Products of reactions 7.3
What happens in a hydration reaction with an alkene
At 300 degrees celsius and with a catalyst of phosphoric acid. a molecule of water (H₂O) is added to an alkene, resulting in the formation of an alcohol.
E.g. Alkene + H₂O —(acid catalyst, heat)→ Alcohol
29
# Alcohols 7.4
How is alcohols solubility is water
Small alcohole is completley soluble in water.
But with an increase size in the alcohole molecule dispersion forces start to change. When the alcohole gets to around 8 carbons i length dispersion forces domiate causing solubility to decline.
30
# Alcohols 7.4
Following the chemical properties of alcohols how can we measure the combustion of alcohols.
Then enthalpy change= -18.6kJ over 0.01975 mol
=-942 KJ per mol
Why isnt this perfect?
Incomplete combustion
Loss of heat
Improve it?
Put spirit lamp in a tube
Force feed oxygen through small holes to get complete combustion.
31
# Alcohols
what are the three structures and classification of alcohols
1. Primary (1°) Alcohol
The carbon with the –OH group is attached to only one other carbon.
Example: Ethanol (CH₃CH₂OH)
2. Secondary (2°) Alcohol
The carbon with the –OH group is attached to two other carbons.
Example: Propan-2-ol (CH₃CHOHCH₃)
3. Tertiary (3°) Alcohol
The carbon with the –OH group is attached to three other carbon atoms.
Example: Tert-butanol (CH₃)₃COH
32
# Alcohol 7.4
How does the dehydration of alcohols using a catalyst work
heat to 170 degrees using a concentrated phosphotic acid solution. Then gasses pass through NaOH to subtract carbon dioxide and sulfur dioxide
E.g.
CH₃CH₂OH —(conc. H₂SO₄, heat)→ CH₂=CH₂ + H₂O
33
# Alcohol 7.4
What happens with reactions involving hydrogen holides and alkenes(HX)
where X is a halogen like Cl, Br, or I—typically occur with alkenes through an electrophilic addition reaction, resulting in a haloalkane (alkyl halide). OH is taken over by a halogen.
34
# Alcohols 7.4.2
How can you oxidise primary alcoholes
You can reflux this reaction since doing it at a higher temperature causes things and reactions to happen more quickley (also dont lose gasses as they drip back in via the flowing water of the structure of refluxing)
35
# Alcohole 7.4.2
How can you oxidise secondary alcohols
They oxidise to keytones but no further than that.
36
# Alcohole 7.4.2
How can you oxidise tertiary alcohols
They cannot oxidise since there is no OH to get taken near the Carbon chain.
37
# Alcohole 7.4.2
How can you identify tertiary alcohole
- tertiary alcohole doesnt change colour when alcohole is put in
- however primary and secondary alcohole does change colour.
38
# Alcohole 7.4.2
how can you dientify the difference vbetween primary and secondary alcohole
Schiffs reagent test where primary becmes magenta and secondary has no colour.
39
# Alcohole 7.4.2
How are alcoholes produced
Halogenoalkanes undergo substitution in warm dilate alkali solution making alcohols.
E.g.
CH₃CH₂Br + NaOH (aq) —(warm)→ CH₃CH₂OH + NaBr
40
# Alcohole 7.4.2
How are Secondary and tertiary alcohols produced with halogenoalkanes
41
# Alcohole 7.4.2
Fermentation
It is only used to produce ethanol.
After the ethanol gets to 15% alcohole the yeast is killed.
Then distillation is used to gt the alcohole out of the yeast mixture.
E.g.
C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂
42
# Alcohole 7.4.2
What is the manufacture of ethanole from ethene equasion
C₂H₄ + H₂O → C₂H₅OH
Through dilute H3PO4
43
# Alcohole
What are the pros and cons of organic source fuels and biofuels
**Biofuels**
Pros:
Energy security
Saving of value finite resources
CO2 brought back into lants and not into atmosphere
Cons:
Plants arnt avalable to be food as all will be used on fuel
**Organc sources**
Pros:
It is better to be sustainable
Cons:
Practically it is harder to use
44
# Alcohole
What is the brainmap of the production of Bioethanol
45
# Different functional groups
Alcohol
–OH
Hydroxyl group
Suffix: –ol
Ethanol – CH₃CH₂OH
46
# Different functional groups
Haloalkane
–Cl, –Br, –I, –F
Halogen atom
Prefix: Chloro–, Bromo- etc.
Chloroethane – CH₃CH₂Cl
47
# Functional groups
Aldehyde
–CHO
Carbonyl at end
Suffix: –al
Ethanal – CH₃CHO
48
# Functional groups
Ketone
>C=O
Carbonyl within chain
Suffix: –one
Propanone – CH₃COCH₃
49
# Functional Groups
Carboxylic Acid
–COOH
Carboxyl group
Suffix: –oic acid
Ethanoic acid – CH₃COOH
50
# Functional Group
Ester
–COO–
Formed from acid + alcohol
Suffix: –oate
Methyl ethanoate – CH₃COOCH₃
51
# Functional group
Amine
–NH₂
Amino group
Prefix: amino– /
Suffix: –amine
Ethanamine – CH₃CH₂NH₂
52
# Functional group
Amide
–CONH₂
Amide group (from carboxylic acid + amine)
Suffix: –amide
Ethanamide – CH₃CONH₂
53
# organic acids and bases 7.5
What are the melting points and solubility of organic acids and bases?
🌿** Organic Acids (e.g. carboxylic acids) solubility**
In Water:
Slightly soluble as neutral molecules because they have polar carboxyl (-COOH) groups that can hydrogen bond with water.
More soluble at high pH: form carboxylate anions (R–COO⁻), which are highly water-soluble due to charge.
In Organic Solvents:
More soluble in non-polar or slightly polar organic solvents
⚗️ **Organic Bases (e.g. amines) solubility**
In Water:
Moderately soluble due to hydrogen bonding with water.
More soluble at low pH: form ammonium ions (R–NH₃⁺), which are highly soluble in water.
In Organic Solvents:
Neutral amines are soluble in organic solvents.
🌿** Organic Acids (e.g. carboxylic acids) melting points**
Generally have higher melting points than comparable hydrocarbons or alcohols due to:
Strong hydrogen bonding between the –COOH groups.
(two molecules hydrogen bond together).
Melting point increases with molecular weight, but:
Branched molecules have lower melting points than straight-chain isomers (less efficient packing).
Even-numbered carbon chains tend to have higher melting points than odd-numbered ones (better packing in the crystal lattice).
⚗️ **Organic Bases (e.g. amines) melting point**
Melting points vary widely depending on structure:
Primary and secondary amines can hydrogen bond, so they often have higher melting points than tertiary amines.
Tertiary amines lack N–H bonds and cannot form H-bonds as donors → lower melting points.
54
# Organic acids and bases 7.5
Primary secondary and tertiary charactaristics
All the same except the Nitrogen is the main aspect. Primary, one hydrogen is removed around the nitrogen, secondary, two hydrogens replaced by hydrocarbon groups around the nitrogen and so on.
55
# Organic acids and bases 7.5
Primary amines
-As chains get longer dispersion forces get more important
- Can form H bonds, dipersion forces and dipole dipole interactions
- this is the most acidic of the amines
56
# Organic acids and bases 7.5
Secondary amines
- Permanent dipole slightly less due to N atom being on middle of chain
- Still form hydrogen bonds
- Lower dipole dipole attractions: lower boiling point
57
# Organic acids and bases 7.5
Tertiary amines
- No H atoms attached to N= no hydrogen bonding= much lower boiling point
- this is the most basic of the amines
58
# Organic acids and bases 7.5
Physical properties of carboxylic acids
- Colourless
- Strong odour
- More than 10 carbon atoms= waxlike solids
- Polar- exhibit strong hydrogen bonding
- High boiling points compared to Molar Mass
59
# Organic acids and bases 7.5
What are esters?
Esters are organic compounds formed when a carboxylic acid reacts with an alcohol. They have the general structure:
R–COO–R’
The R group comes from the acid
The R' group comes from the alcohol
60
# Organic acids and bases 7.5
What is the esterification reaction
Carboxylic Acid+Alcohol
with (H⁺, heat)
=.
Ester+Water
You make this under a reflux
61
# Organic acids and bases 7.5
What is Reflux?
Its basically heating stuf together and letting the vapost come back down by cooling the area with flowing water
62
# Organic acids and bases 7.5
What are the charactaristics of amides?
| Melting point and reaction equsion
-There are 4 places to bond to hydrogen making it have a high melting point
- You make it by:
Carboxylic Acid+Amine (or NH2)
with Heat
=.
Amide+Water
63
# Organic acids and bases 7.5
What are the charactaristics of ammonium salt?
-Ammonium salt splits into its parent acid (acetic acid) when heated, and recombines in cooling since its a equilibrium reaction
CH₃COOH (aq)+NH₃ (aq)⇌CH₃COO⁻ (aq)+NH₄⁺ (aq)
64
# Organic acid and bases 7.5
How is ethanamide produced
Ethanamide is made bu ethanoyl acid and concentrated ammonia in water.
65
# Organic acids and bases 7.5
How do you turn amide into primary amine?
Reduced: Add hydrogen (take out O)
Also needs catalyst
66
# Organic acids and bases 7.5
What happens if you do the amide into primary amine solution under acidic conditions?
- It will not work and produce ammonium and a carboxylic acid
R–CONH₂+H₂O
H⁺, heat
=.
R–COOH+NH₄⁺
67
# Organic Acids and bases 7.5
What happens if you do the amide into primary amine solution under basic conditions?
- you get A carboxylate ion and Ammonia gas
- CH₃CONH₂+OH⁻
heat
=.
CH₃COO⁻+NH₃
68
# organic acids and bases 7.5
What is glycerol?
| Charactaristics, structure, from what
-Fats and oils are esters or glycerol and fatty acids
69
# Soap 7.6
What is the esterification reaction?
Esterification is a condensation reaction between a carboxylic acid and an alcohol, producing:
An ester
Water (H₂O)
It’s called a condensation reaction because a small molecule (water) is removed when two molecules join.
Reaction:
Carboxylic acid+Alcohol
H⁺, heat
=.
Ester+Water
70
# Soap 7.6
What is suponification?
Changing a triglycarde into glycerole and salts of fatty acids.
71
# Soaps 7.6
Soap structure
72
# Soap 7.6
Structure of detergents
73
# Soap 7.6
How does the non-ionic soap work?
| What is it used for compared to normal soap
74
# Soap 7.6
How does less bubbled soap work?
75
# Soap 7.6
Micelle structure
