Module 7: Organic Chemistry Flashcards
What is polymerisation?
When monomers combine to form polymers
What are monomers?
Smaller single molecular units
What are polymers?
Larger and long covalent molecular substances made of repeated monomer units.
What is the IUPAC name of polyethylene?
Polyethene
What is the structural formula of polyethylene?
(H2-C-C-H2)n
What monomer is used for polyethylene?
Ethylene
What is the structural formula of ethylene?
H2-C=C-H2
What is addition polymerisation?
The formation of addition polymers without any loss of atoms
How does the addition process works?
The double bond open out to form bonds with the neighbouring molecules
Which hydrocarbons are extremely flammable?
Short chain alkanes, alkenes and alkynes
Why are short chain hydrocarbons more volatile?
Less number of dispersion forces and intermolecular forces
What is the impact of high concentration of hydrocarbons?
It is toxic to humans
How are gas hydrocarbons safely stored?
They are kept in well maintained cylinders and fitting
What do gas hydrocarbons have to easily detect leakage?
There is an addition of odours
How are liquid hydrocarbons safely stored?
In sturdy containers
What storage methods should be kept in mind when keeping hydrocarbons?
Minimal quantities should be stored and used and should be kept away from naked flames
How are hydrocarbons safely transported?
They are transported in reinforced steel that can withstand high impacts
What is a risk during transportation of hydrocarbons and how is it minimised?
The risk of static electricity buildup which is reduced with a static electricity dissipation device
How are hydrocarbons safely stored in cars?
The fuel tanks are located at the opposite end of the vehicle away from the engine
What colour is kerosene coloured?
Blue
What colour is unleaded fuel?
Yellow
Why is hydrocarbon fuel coloured?
It provides a quick way of identification in the case of spilling
How are organic substances disposed of at school?
Usually they are collected and disposed separately after use in the school lab
How should containers which held organic substances be disposed of?
They must be collected by licensed waste management operators
What type of impact do hydrocarbons have on the environment?
Negative impacts
What is an impact of hydrocarbon use on the environment?
An increased concentration of CO2 in the atmosphere contributing to global warming
What is an impact of hydrocarbon extraction on the environment?
Spills and destruction of environments can have great impact on the environment
What type of impact do hydrocarbons have on the economy?
Largely positive incomes
What is an impact of hydrocarbon use have on the economy?
Has provided a huge output of energy providing a reliable source of energy for industry
What is an example of an industry which has boomed from hydrocarbon use?
Long haul transportation industries
What type of impact do hydrocarbons have on sociocultural factors?
Both positive and negative
What are some positive impacts of hydrocarbons on sociocultural factors?
Development of advanced drugs and pharmaceuticals, efficient and cheap heating, town electricity increases productivity
What are some negative impacts of hydrocarbons on sociocultural factors?
Exposure can lead to health issues, increasing cost associated with landfill, dependency on hydrocarbons
What do all addition polymerisation have in common?
The monomers all have a double bond which open out to form single bonds with neighbouring molecules and there is no loss of atoms
What are the two production techniques of polyethylene?
Gas phase process
Ziegler-Natta process
What is the polyethylene called made using the gas phase process?
Low Density Polyethylene LDPE
What is the polyethylene called made using the zieglar natta process?
High Density Polyethylene HDPE
What does LDPE end up with?
Produces significant side chain branching
What does HDPE end up with?
No side chain branching
What is the IUPAC name for polyvinylchloride?
Vinylchloride
What monomer is polyvinylchloride made from?
Chloroethene
What is the structural formula of chloroethen?
CH2 = CH - Cl
What is the structural formula of polyvinylchloride?
(CH2-CH)n
|
Cl
What is the IUPAC name of polystyrene?
Styrene
What monomer is polystyrene made of?
Styrene
What is polystyrene used for?
Packaging material, coffee/milkshake cups
What is the polytetrafluoroethylene also known as?
Teflon
What monomer is polytetrafluoroethylene made of?
Tetrafluoroethylene
What is the structure of tetrafluoroethene?
F2-C=C-F2
What is the structure of polytetrafluoroethylene?
(F2-C=C-F2)n
What is polytetrafluoroethylene used for?
Non-stick frying pans
What is the impact of side chain branching?
Lower the density of the polymer, low MP’s and BP’s and tend to be soft and flexible and clingy
What are polymers with side branching called?
Non-crystalline/amorphous
What is the impact of no side chain branching?
Higher density of polymer, high MP’s and BP’s and tend to be hard, rigid, inflexible and tough
What are polymers without side branching called?
Crystalline
What is chain stiffening?
Some polymers with side branching whilst having a lower density will have an overall stiffness to them
What are some examples of polymers with chain stiffening?
PVC and polystyrene
Why are addition polymers insoluble in water?
They have a high molecular weight, are non-polar and have a lack of hydrogen bonding
What is PVC susceptible to?
UV light which can break C-Cl bonds
Where does PTFE get its slipperiness from?
The polar C-F bonds and the subsequent dipole-dipole bonds that form between neighbouring chains
What is condensation polymerisation?
Occurs in the absence of a double bond and almost always releases a water molecule
When can a condensation polymer occur?
If the monomer has two terminal functional groups ie OH and COOH
How many water molecules produced during condensation polymerisation?
One less than the number of monomers in the chain
What is the monomer of polyester?
2-hydroxypropanoic acid
What are the terminal functional groups of the monomer of polyester?
OH and COOH
What link is formed during the formation of polyesters?
An ester link
What are the terminal functional groups of the monomer of nylon?
COOH and NH2
What link is formed during the formation of nylon?
An amide link
What type of structure can carbon form?
Long chain, branch chain and ring structures
What type of bonds do carbons form with each other and non metals?
Covalent compounds
How strong are carbon bonds?
Generally strong
What is bond energy?
The amount of energy required to break a bond
What are the four ways to represent organic molecules?
Molecular formula, structural formula, condensed formula and skeletal structure
What does the molecular formula look like?
C2H6O
What is an advantage of the molecular formula?
Indicated the number and type of atoms present
What is a disadvantage of the molecular formula?
Does not show any structure or bonding
What does the structural formula look like?
Structure drawn out
What is an advantage of the structural formula?
Shows location of atoms and it shows the number and location of covalent bonds
What is a disadvantage of the structural formula?
Tedious to draw all atoms involved
What does the condensed formula look like?
CH3CH2OH
What is an advantage of the condensed formula?
Show connections and carbon chain as one line
What is a disadvantage of the condensed formula?
No 3D arrangement or bonding shown
What are hydrocarbons?
A class of carbon compounds that contain carbon and hydrogen
What is an aromatic hydrocarbon?
One that contains one or more benzene rings
What is an aliphatic hydrocarbon?
One that does not contain any benzene rings
What is a homologous series?
A series of organic compounds in which each member differs by a CH2 unit
What are alkanes?
Hydrocarbons that contain only single bonds
What is the general formula of alkanes?
CnH2n+2
Are alkanes saturated or unsaturated?
Saturated compounds with no double or triple conds
What are alkenes?
Hydrocarbons that contain a double bond
What is the general formula of alkenes?
CnH2n
Are alkenes saturated or unsaturated?
Unsaturated
What are alkynes?
Hydrocarbons that contain a triple bond
What is the general formula of alkynes?
CnH2n-2
Are alkynes saturated or unsaturated?
Unsaturated
What are alkyl branch groups?
Side branch chains
How are alkyl branch names named?
Prefix indicates the number of carbon atoms in the side chain and suffix -yl used
What are cyclic hydrocarbons?
Carbon atoms that have formed a ring
What are the four common cyclic hydrocarbons?
Cyclopentane
Cyclohexane
Cyclopentene
Cyclohexene
What is the 5 steps of nomenclature?
- Select the longest carbon chain and name it
- IF C=C or C≡C present use appropriate suffix and indicate position with a number
- If branch chains present number from shortest chain and put name in front
- If multiple side chains number all and add appropriate prefix
- If there are different branch chains write them alphabetically
How do you name halohydrocarbons?
Add prefix fluro-, chloro-, bromo-, iodo-
What is present in a halohydrocarbon?
Halo
How do you name alcohols?
Add suffix -ol
What is present in an alcohol?
Hydroxyl -OH
How do you name an aldehyde?
Add suffix -al
What is present in an aldehyde?
Carbonyl -CO at the end of carbon chain
How do you name a ketone?
Add suffix - one
What is present in a ketone?
Carboxyl -CO not at the end of a carbon chain
How do you name a carboxylic acid?
Add suffix -oic acid
What is present in a carboxylic acid?
Carboxyl -COOH
How do you name an ester?
Add suffix -yl …. - oate
What is present in an ester?
Ester -COOC-
How do you name an amine?
Add suffix - amine
What is present in an amine?
Amino - NH2
How do you name an amide?
Add suffix - amide
What is present in an amide?
Amide -CONH2
Why is a double bonded oxygen to carbon significant?
As it will always be counted as 1 in the carbon chain
What is the order of priority when naming compounds?
- Carboxyl
- Hydroxyl
- Amine
- Alkene
- Alkyne
- Halo
What are halokanes?
Alkanes with one or more hydrogens replaced
What are haloalkanes usually used for?
Fire extinguishers, refrigerants, propellants, pesticides and solvents
What are the three classifications of alcohols?
Primary, -OH bonded to one alkyl group
Secondary, -OH bonded to two alkyl groups
Tertiary, -OH bonded to three alkyl groups
What is the simplest aldehyde?
Methanal also known as formaldehyde
What is the simplest ketone?
Propanone also known as acetone
Where are carboxylic acids commonly found?
In nature
What are esters responsible for?
Flavours and smells
How are esters made?
Reaction between a carboxylic acid and an alcohol
What does an esters name contain?
Two words consisting of the alcohol and acid
What can amines and amides by classified as?
Primary, secondary and tertiary
What do amines usually occur as?
Amino acids in nature
How are amides formed?
Reacting carboxylic acid with an amine
What are isomers?
Molecules that contain the same number and type of atoms but are arranged in different ways
What are chain isomers?
Isomers possible due to branching of hydrocarbons
What are position isomers?
Isomers that exist when carbon compounds contain functional groups
What are functional group isomers?
Isomers with the same molecular formula but different functional groups
What are the three main factors that determine physical properties of hydrocarbons?
Intermolecular forces between the molecules, size of the molecules and shape of the molecules
What is the boiling point of alkanes and why?
Low BP as they are non-polar and have weak dispersion forces
What is the boiling point of alkanes and why?
Low BP as they are non-polar and have weak dispersion forces
How does chain length impact BP?
As chain length increases the BP increases as there are more attraction forces holding the molecules closer together
Does straight chain or branch chain hydrocarbons have a higher BP?
Straight chain as they can fit closer together
How does chain length impact melting point?
As chain length increases melting point increases
Do carbon chains with even or odd carbon atoms have a higher MP?
Even as they can pack slightly closer together
What else can impact melting point?
Double or triple bond can affect MP
What is the solubility of alkanes, alkenes and alkynes in water?
They are insoluble in water due to non-polar nature compared to polar nature of water
What is the BP of haloalkanes?
Slightly higher than alkanes due to the halogen carbon bond that allows dipole-dipole attraction
Are alkanes, alkenes and alkynes soluble or insoluble in water and why?
They are insoluble due to their non-polar nature compared to polar nature of water
How soluble are haloalkanes in water and why?
Only slightly more soluble than alkanes, alkenes and alkynes due to their more polar nature
What is the density of haloalkanes?
Higher density than water hence settle below water
Are alkanes, alkenes and alkynes soluble in organic solvents and why?
They are soluble as they are both non-polar
Are haloalkanes soluble in organic solvents?
Yes as they have the same dispersion forces
What is crude oil?
A mix of hydrocarbons formed by geological activity
How is crude oil separated?
Using fractional distillation
How does fractional distillation work?
Since BP increases as molecular weight increases separation occurs in weight order
What is the combustion reaction?
Alkanes and alkenes undergoing combustion to produce CO2 and H2O
Which one is more reactive alkenes or alkanes?
Alkenes
What is a substitution reaction?
When a hydrogen atom is substituted by a halogen atom on an alkane
What is required for a substitution reaction?
UV light shown on top of the arrow
What is an addition reaction?
Double bond in an alkene breaks open to react with other substances
What is required for a substitution reaction?
A catalyst
How do you distinguish between an alkane and an alkene?
Add bromine water to a sample of alkane and alkene. In the dark only the alkene will react turning from red to clear
What is the oxidisation of an alkene?
The reaction of an alkene with a potassium permanganate
What is the formula for potassium permanganate?
KMnO4
Where should the potassium permanganate be put in an oxidisation reaction?
Above the arrow
What happens in an oxidisation reaction with cold KMnO4?
Produces dialcohols
What happens in an oxidisation reaction with hot KMnO4?
Produces a carboxylic acid or ketone
What is unique about the oxidisation reaction with hot KMnO4?
It usually occurs in two or three steps
What is the boiling point of alcohols and why?
Have higher BP than similar alkane length molecules due to strong covalent bonds and hydrogen bonding
Is alcohol soluble in water and why?
It is generally soluble in water due to the hydrogen bonding between polar water molecules and polar alcohol
How does carbon chain length impact alcohol solubility in water?
As carbon chain increases the molecules become more non-polar hence solubility decreases
How does carbon chain length impact alcohol solubility in organic solvents?
As carbon chain increases the solubility increases short chain alcohols are not soluble
How can alcohol be formed?
Fermentation or substitution
How can alcohol be formed with substitution?
Be reacting haloalkanes with hydroxide ions or with water
What is required for the substitution reaction of a haloalkane with water to produce alcohol?
Requires a catalyst put on top of the arrow
What type of process is fermentation?
An anaerobic process
What is the most common method of fermentation?
The breakdown of glucose with yeast to produce ethanol and CO2
What are the steps in fermentation?
- Yeast mixed with grain or fruit slurry
- Air is excluded
- Mixture maintained at 37 degrees c
- When ethanol reaches 15% yeast dies
- Filtration and distillation to increase conc and purity of ethanol
What is the chemical formula for glucose?
C6H12O6
What are the four most common materials used for fermentation?
Starchy grains, tubers, fruits and molasses
What do monosaccharides contain?
Carbon, hydrogen and oxygen
What are polysaccharides?
Complex carbohydrates made up of monosaccharides
How to calculate the heat of combustion?
Use formula q=mcAT to find q and then use formula q/change in mass
What is heat of combustion always measured in?
KJ/g
What do all the letters in q=mcAT mean?
q - energy absorbed by water
m - mass of water
c - specific heat capacity of water
AT - temp change
What is required for the oxidisation of alcohols?
H+/MnO4-
What are two strong inorganic oxidising agents which can be used for the oxidisation of alcohol?
Acidified potassium permanganate
Acidified potassium dichromate
What is the chemical formula for acidified potassium dichromate?
K2Cr2O7
What is formed in a primary alcohol oxidisation?
Initially forms an aldehyde which can then further oxidise to form a carboxylic acid
If an aldehyde is desired what should be done in the oxidisation of a primary alcohol?
Lower temp and shorter time used
If an acid is desired what should be done in the oxidisation of a primary alcohol?
Higher temp and longer time used
What is required above the arrow for an oxidisation reaction of a primary alcohol?
H+/MnO4-
What is formed in a secondary alcohol oxidisation?
A ketone
What is required above the arrow for an oxidisation reaction of a secondary alcohol?
H+/MnO4-
What is formed in tertiary alcohol oxidisation?
They resist oxidisation and do not react
What is a dehydration reaction?
A type of elimination reaction where water is removed from an alcohol
What is required for a dehydration reaction?
Concentrated H2SO4 or H3PO4
What is a substitution reaction of alcohol?
When an alcohol reacts with hydrogen halides to form an alkyl halide and produce water
What is a condensation reaction?
When carboxylic acids and alcohols react to form esters and water
What is required in a condensation reaction?
A catalyst, concentrated H2SO4 and an equilibrium arrow
What are non-renewable resources?
Resources formed in the environment over a very long time and can be exhausted
What are renewable resources?
Naturals resources which replenish after being used and will never be depleted
What is a sustainable resource?
Something that will never run out and has a lower impact on the environment
What are fossil fuels?
Fuel made from decomposing plants and animal which can be found in the the Earth’s crust
What are biofuels?
Fuel made from biomass
Advantages of using bioethanol as a renewable fuel?
Is a liquid hence easy to transport, is a renewable resource, could reduce CO2 emissions and burns more cleanly and completely
Disadvantages of using bioethanol as a renewable fuel?
Large areas of land needed to grow suitable crops and disposal of a large volume of smelly fermentation waste liquid
What is the BP of carboxylic acids, amines and amides?
Have higher BPs than alkanes due to their functional groups being able to create hydrogen bonds
What is the BP of aldehydes and ketones?
Have higher BPs than alkanes but lower than carboxylic acids due to their dipole-diploe forces
Does an amide or an amine have a higher BP?
Amides since they have more hydrogen bonds
Why do carboxylic acids have a considerably higher BP?
As their hydrogen bonding can form a dimer structure which is when two carboxylic acids form two hydrogen bonds
Do amides follow the pattern for BP and chain length relativity?
No as amides form more complicated bonds
Are carboxylic acids, amines and amides soluble in water?
Short chains are soluble is water due to their partial positive charge of the hydrogen which is attracted to the partial negative oxygen
How does carbon chain length impact solubility of carboxylic acids, amines and amides in water?
As chain length increases solubility in water decreases
Are carboxylic acids, amines and amides soluble in organic solvents?
Short chains are insoluble in organic solvents but as chain length increases they become more soluble
Will carboxylic acids dissociate in water?
They are weak acids so they will only dissociate a little hence they need an equilibrium arrow
Through what process are esters formed?
Through a condensation reaction known as esterification
What is additionally used in labs to produce esters?
Heat and H2SO4
What does H2SO4 do during esterification?
Acts as a catalyst lowering the activation energy and is a strong dehydrating agent removing water produced
What is the refluxing process?
The process of heating a mixture with a cooling condenser so there is no loss of mixture
What does refluxing do?
Increases the rate of reaction and increases yield of products
What type of reaction is the reaction between carboxylic acid and ammonia?
Is a condensation reaction that produces a primary amide
What type of reaction is the reaction between carboxylic acid and amines?
Is a condensation reaction that produces a secondary amide
What is the difference between amine and amide reactivity?
- Amines are more reactive than amides and act as organic bases
- Amines dissociate in water
- Amides do not act as acids or bases
- Amides are less soluble in water
What are fats and oils?
Are esters of glycerol and fatty acids
What is glycerol?
A triple alcohol derivative of propane
What are fatty acids?
Are long carbon chain acids which are saturated or unsaturated
What are fats and oils also known as?
Triglycerides as there are three fatty acids
What is the difference between saturated and unsaturated fatty acids?
Saturated are unreactive and have a higher melting point
Unsaturated are more reactive, have a lower melting point and are healthier
What is saponification?
Involves the hydrolysis of fats. Triglycerides are reacted with sodium or potassium hydroxide to form an alcohol and a salt of a fatty acid
What is the structure of soap?
Long hydrocarbon tail is non-polar and hydrophobic
Negatively charged carboxyl head is polar and hydrophilic
What are micelles?
When the hydrophobic tails are on the inside and hydrophilic heads are on the outside
How does soap work?
Hydrophobic tails dissolve in grease surrounding it allowing the grease to float in the water off the fabric or skin
What monomer forms polypropene?
Propene
What is the structure of propene?
H2C=CH-CH3
What is the structure of polypropene?
(H2C-CH)
|
CH3
What are thermoplastics?
Polymers which can soften and become mouldable when heated
What is considered a thermoplastic?
Polyethene, polypropene, PVC and nylon
What are thermosettings?
Polymers which decompose or burn when heated
What is considered a thermosetting?
Epoxy, silicone
What are elastomers?
Polymers with elastic properties as the polymer chains can still move past each other
How many chain isomers does pentane have?
3
What is the general formula for cycloalkanes?
CnH2n
What is the general formula for cycloalkenes?
CnH2n-2
What substance would increase the yield of the product during esterification?
More alkanol
What is the colour change of the oxidisation of butanol?
Purple to colourless
What is the colour change of the oxidisation of ethanol?
Orange to green
What bond angle does an alkyne have?
180 degrees
How do Aboriginal and Torres Strait Islander peoples remove toxins from cycad plants?
Fermentation and leaching
How does the process of leaching work to get rid of toxins in cycad plants?
Seeds are crushed and put in mesh bag and placed in flowing river. Toxins are polar due to OH making them soluble in water and are washed away
Why are pH probes better than indicators?
The use of an indicator is a destructive test and observing the colour change is subjective
What is the word equation for saponification?
triglyceride + sodium hydroxide –> alcohol + fatty acid salt
What is a surfactant?
Another name for soaps and detergents
What does a surfactant do?
Lowers the surface tension of water by interrupting hydrogen bonding
How are soaps and detergents emulsifiers?
They can cause immiscible samples of oil and water to undergo emulsion and mix together
How does the hydrophobic tales of soap molecules bond with grease?
Via dispersion forces
How does the hydrophilic head of soap molecules bond with water?
Via Dipole diploe attraction