Module 4: Core Organic Chemistry V1 Flashcards
Define what is meant by a “saturated compounds”
Has only single bonds and no C=C double/ multiple bonds. ✓
Define what is meant by a “Hydrocarbon”
Compound consisting of carbon and hydrogen atoms only ✓
Define what is meant by an “aliphatic compound”
Where the carbon atoms are joined together to form a straight chain. (branched or unbranched) ✓
Define what is meant by an “unsaturated compound”
Contains at least one carbon - carbon multiple bonds. ✓
Define what is meant by an “alicyclic compound”.
Where the carbon atoms are joined together in a ring structure. (branched or unbranched) ✓
Define what is meant by an “aromatic compound”
Compound which contains a benzene ring –C6H5 .✓
Classify the following molecules as being either:
a) Saturated or unsaturated
b) Aliphatic or alicyclic
c) Aromatic
Classify the following molecules as being either:
a) Saturated or unsaturated
b) Aliphatic or alicyclic
c) Aromatic
Note: the branch part is aliphatic
State the general formula for alkanes
Give the formula for an alkane containing 5 carbon atoms
Give the formula for an alkane containing 14 H atoms.
Systematically name the following:
2-methylbutane ✓ 2,2-dimethylpropane ✓
2,3,4-trimethylpentane ✓ 2,3,4,4-tetramethylhexane ✓
Systematically name the following:
Butane-1,3-diene ✓ Cyclopentane ✓
Cyclopentene ✓ Methylcyclohexane ✓
4,5,6,6-tetramethyloct-1-ene ✓
Systematically name the following:
1-bromo-2-fluoropropane ✓
bromochlorofluoroiodomethane ✓
1,1,2,2-tetrachloroethane ✓
2-chloro-3-methylbutane ✓
2-chloro-3-hydroxy-3-methylbutanoic acid ✓
5-hydroxypentanoic acid ✓
Draw the structure, using skeletal formula of the following compounds:
1. 2-bromopropane
2. 1,1,1-tribromopropan-2-ol
3. propanoic acid
4. butane-1,2-diol
5. 1,3-diiodopropane
6. 2-hydroxypropanoic acid
7. 2,3-dimethylhexanoic acid
8. 2-fluoro-3-iodobutanoic acid
9. cyclohexanol
10. 1,2-dichlorocyclopentane
11. 5. 3,4,5,6,7-pentamethyloctanoic acid
Give the structural formula for the following: 1. octane
2. ethanol
3. but-1-ene
4. propanoic acid
5. pentan-2-one
6. 2-bromopentane
7. hexanal
8. 2-methylpropene
Define what is meant by “structural isomers”
compounds with the same molecular formula… ✓ but different structural formulae ✓
Pentane is an isomer of 2-methylbutane. State and explain the type of isomerism between the two compounds.
Structural isomersim. ✓
Compounds with the same molecular formula… ✓
but different structural formulae ✓
Chain isomerism, ✓ where carbon chains can be branched or unbranched. ✓
butan-1-ol is an isomer of butan-2-ol. State and explain the type of isomerism between the two compounds.
Structural isomersim. ✓
Compounds with the same molecular formula… ✓
but different structural formulae ✓
Positional isomerism, ✓ where functional groups can be at a different position. ✓
propanone is an isomer of propanal. State and explain the type of isomerism between the two compounds.
Structural isomersim. ✓
Compounds with the same molecular formula… ✓
but different structural formulae ✓
Functional group isomerism, ✓ where functional groups can different. ✓
Hex-1-ene is an isomer of cyclohexane. State and explain the type of isomerism between the two compounds.
Structural isomersim. ✓
Compounds with the same molecular formula… ✓
but different structural formulae ✓
Functional group isomerism, ✓ where functional groups can different. ✓
Pen-1-yne is an isomer of cyclopentene and cyclopentane-1,3-diene. State and explain the type of isomerism between the three compounds.
Structural isomersim. ✓
Compounds with the same molecular formula… ✓
but different structural formulae ✓
Functional group isomerism, ✓ where functional groups can different. ✓
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Draw the structure of all possible isomers of the following:
(note: naming them prevents you from making duplicate isomers, remember to follow the rules you don’t make mistakes i.e. “pentane vs 1-methylbutane”)
Determine the general formula for the following compounds (each row)
Note: You may wish to compare the pattern (change in molecular formula) to the alkanes general formula.
What is the number of alicyclic structural isomers of C5H10?
- Cyclopentane
- methylcyclobutane
- ethylcyclopropane
- 1,2-dimethylcyclopropane
- 1,1-dimethylcyclopropane
- ✓
The systematic name for halothane is 2-bromo-2-chloro-1,1,1-trifluoroethane.
Draw the structure of a halothane molecule.
✓
What is the number of fluorine atoms in 7.896 g of 2-bromo-2-chloro-1,1,1-trifluoroethane. Give your answer to 4 significant figures.
Explain why alkanes are generally unreactive.
Molecules are non-polar (no dipoles) ✓
C-C and C-H bonds have high bond enthalpies ✓
Define what is meant by a “sigma bond”
Caused by the end-on-end overlap of bonding orbitals ✓ directly between atoms ✓
State and explain the shape around the carbon atoms in a molecule of hexane. Include a bond angle in your answer.
Tetrahedral ✓
109.5 degrees ✓
There are 4 bonded pairs and 0 lone pairs around the C atoms ✓
All electron pairs repel ✓
Describe and explain how boiling points changes as carbon chain length in a straight chain alkane increases
As chain length/ number of carbon atoms increases ✓… boiling and melting points increases. ✓
Largermoleculeshave more points of surface contact between molecules. ✓
Strength of induced dipole-dipole interactions increases betweenmolecules, which requires more energy to overcome. ✓
Describe and explain how boiling point changes as the number of branches in an isomer molecule increases
Themorebranchesin anisomermolecule, the lower the boiling point ✓
The lesspointsofsurfacecontactwith each other… ✓
The weaker induced dipole-dipole interactions between molecules which require less energy to overcome ✓
Explain why decane has a higher boiling point than pentane
Decane has more carbon atoms. ✓
Decane is largerandhas more points of surface contact between molecules. ✓
Decane has stronger of induced dipole-dipole interactions increases between molecules, which requires more energy to overcome. ✓
Explain why 2,3-dimethylbutane has a lower boiling point than hexane
Hexane has less branches than 2,3-dimethylbutane but the same number of carbon atoms ✓
Hexane has morepointsofsurfacecontactbetween molecules ✓
Hexane has stronger induced dipole-dipole interactions between molecules which require more energy to overcome ✓
Write a balanced equation for the complete combustion of ethane
CHO
Write a balanced equation for the complete combustion of ethanol
CHO (don’t forget the O in ethanol)
Write a balanced equation for the complete combustion of octane
Write a balanced equation for the complete combustion of a mixture of ethanol and octane, where the ratio of ethanol: octane is 1:1
Explain why branched chain alkanes are preferred for fuels compared to straight chain alkanes
They have more efficient combustion ✓
State a hazard associated with carbon monoxide.
Carbon monoxide is poisonous ✓
Define what is meant by “complete combustion” and give the balanced equation for complete combustion of methane
Burning of a substance in excess supply of oxygen ✓
Define what is meant by “incomplete combustion” and give two balanced equations for incomplete combustion of methane. One to form CO and water only and another to form a solid product and water only.
burning of a substance in limited supply of oxygen ✓
Define what is meant a “radical”.
highly reactive species with an unpaired electron ✓
Define what is meant by “homolytic fission”.
Covalent bond breaks and one electron goes to each atom forming two radicals ✓
During radical substitution, in the initiation step, the type of bond fission taking place is homolytic fission. Explain why.
covalent bond breaks and one electron goes to chlorine atom forming two chlorine radicals ✓
Define what is meant by “heterolytic fission”.
Covalent bond breaks and both electrons go to the same atom forming two ions ✓
During the alkali hydrolysis of 2-bromopentane, the type of bond fission taking place in the C-Br bond is heterolytic fission. Explain why.
Covalent bond breaks and both electrons go to the bormine atom forming a bromine ion. ✓
Methane can be reacted with chlorine to form chloromethane. State the conditions required.
UV. ✓
High temperature. ✓
Methane reacts with chlorine by radical substitution.
Describe fully, with equations, the mechanism for this reaction.
Show all possible termination steps and include an overall equation in your answer.
Ethane reacts with chlorine by radical substitution.
Describe fully, with equations, the mechanism for this reaction.
Show all possible termination steps.
Bromomethane reacts with bromine by radical substitution.
Describe fully, with equations, the mechanism for this reaction.
Show all possible termination steps
Note: Starting material is bromomethane. you’re going to do substiution for the second time to make dibromomethane.
Cyclopentane reacts with chlorine by radical substitution
Describe fully, with equations, the mechanism for this reaction.
Show all possible termination steps
Ethanoic acid, CH3COOH reacts with bromine by radical substitution.
Describe fully, with equations, the mechanism for this reaction. Use structural formula only.
Show all possible termination steps
Note: You cannot susbtitute the carboxyl H.
Chlorine reacts with methane in the presence of UV. State the mechanism of this reaction and the bond fission taking place.
Free radical substitution. ✓
Homolytic bond fission. ✓
Iodine can react with methane in a substitution reaction. This reaction gives a mixture of products. How could the concentration of iodomethane in the final mixture be increased?
Excess methane ✓
Iodine can react with methane in a substitution reaction. This reaction gives a mixture of products. How could the concentration of tetraiodomethane in the final mixture be increased?
Excess iodine ✓
Propanoic acid can also react with bromine with a free radical substitution mechanism. Write the overall equation for this reaction, using molecular formula only.
Propanoic acid can also react with bromine with a free radical substitution mechanism. Draw the structure of both plausible radical intermediates in the propagation step.
Propanoic acid can also react with bromine with a free radical substitution mechanism. Draw the structure of all possible monosubstituted products
Note: Monosubstituted is where 1 H is swapped for 1 group/ halogen (in this case Br). You cannot swap the carboxyl H.
Cyclohexane, C6H12 can undergo free radical substitution with chlorine to form a mixture of products. Using skeletal/ displayed formula only, write an equation to show the formation of chlorocyclohexane.
Cyclohexane, C6H12 can undergo free radical substitution with chlorine to form a mixture of products. Using skeletal/ displayed formula only, write equations to show the mechanism for the reaction to form chlorocyclohexane only.
Cyclohexane, C6H12 can undergo free radical substitution with chlorine to form a mixture of products. Using skeletal/ displayed formula only, write equations to show all three possible termination steps.
State why UV radiation can be hazardous.
Can cause sunburn and skin cancer ✓
Using equations, explain how ozone is formed in the stratosphere and explain how it protects people from UV radiation.
What is a “Chlorofluorocarbon, CFC”
Compound containing chlorine, fluorine and carbon only where all hydrogens replaced ✓
State 4 properties of CFC’s
Stable ✓
volatile ✓
non-flammable ✓
non-toxic ✓
State 4 uses of CFC’s (in the past)
Aerosol cans ✓
dry cleaning ✓
air-conditioning ✓
fridges ✓
Dichlorodifluoromethane, CCL2F2, causes the breakdown of the ozone layer.
Using equations, describe how.
Include the initiation step, propagation steps and overall equation in your answer.
State the catalyst which catalyses the breakdown of Ozone.
Write equations to show how NO radicals destroy the ozone layer
State two sources of NO radicals in the stratosphere.
Aircraft engines ✓
Thunderstorms ✓
NO radicals destroy the ozone layer. Give the overall reaction equation.
R radicals destroy the ozone layer. Using equations show how. Include an overall equation in your answer.
OH radicals destroy the ozone layer. Using equations show how. Include an overall equation in your answer.
State and alternative to using CFC’s. Give an advantage and disadvantage to their use.
HCFC’s or HFC’s. ✓
HCFC’s are broken down in the atmosphere more quickly. ✓
HCFC’s and HFC’s are greenhouse gases. ✓
Alcohols can be synthesized from haloalkanes. State the reagents required and the name of the reaction taking place.
Warm aqueous NaOH or KOH ✓
Reflux ✓
Alkali hydrolysis ✓
1,2-dichloropropane reacts with warm aqueous KOH (under reflux) to form a diol. Draw a mechanism for the reaction, including a balanced equation.