Organic chemistry - Yr 12 content

Question 1

what is a cyclic hydrocarbon

Answer 1

when hydrocarbons adopt a cyclic or ring structure, for saturated each carbon is bonded to two hydrogens and two other carbons

Question 2

how to name cyclic hydrocarbons

Answer 2

the cyclo prefic indicates a cyclic structure, the suffic/second part of the name describes the total number of carbons in the ring structure

Question 3

benzene

Answer 3

cyclic hydrocaebon (C6H6) that is found in petrochemicals, its structure gives its belonging to a class of compounds called aromatic compounds

Question 4

structure of benzene

Answer 4

similar to cyclohexane, but each carbon is only bonded to one hydrogen and shares one double bond, the six carbon atoms adopt a triganol planar geometry, resulting in the entire molecule being flat or planar. the delocalised electrons gives benzene extra stability compared to typical alkenes

Question 5

why are molecules with more than one double bond considered to have a higher degreee of unsaturation

Answer 5

because a greater number of H atoms could be added to them

Question 6

what are molecules with a higher degree of unsaturation called (more than one double bond)

Answer 6

polyunsaturated

Question 7

Degree of unsaturation

Answer 7

DoU = the number of double bonds (including C=O) + the number of cyclic strudtures

Question 8

DoU calculation formula

Answer 8

2C + 2 + N - H -X / 2, C: carbons, N: nitrogens, H: hydrogens X: Halogens

Question 9

how to name and give carbon number to haloalkane with multiple halogens

Answer 9

state the halogens in alphabetical order when naming, give the lowest carbons to the the halogens with the highest electronegativity (highest in group)

Question 10

primary alcohol

Answer 10

the carbon is bonded to the hydroxyl is bonded to one other alkyl group/carbon at most

Question 11

secondary alcohol

Answer 11

the carbon bonded to the hydroxyl group is bonded to 2 other alkyl groups/carbons

Question 12

tertiary alcohol

Answer 12

the carbon bonded to the hydroxyl group is bonded to 3 other alkyl groups/carbons

Question 13

bond strength is aka

Answer 13

average bond energy

Question 14

bond strength

Answer 14

the amount of energy required to break apart one mole of a covalent bond in the gas state

Question 15

bond length

Answer 15

the distance between the nuclei of the atoms sharing the electrons

Question 16

what happens when the number of bonds between the atoms increases

Answer 16

bond strength increases

Question 17

bond strength trend of 1 atom bonded to elements going down the group

Answer 17

bond strength decreases down the same group as the atomic radius of the atom increases and so does the bond length (therefore weaker)

Question 18

3 types of isomers

Answer 18

skeletal/chain isomers, positional isomers and functional group isomers

Question 19

skeletal/chain isomers

Answer 19

molecules have the same molecular formula but different carbon structures

Question 20

positional isomers

Answer 20

molecules have the same molecular formula but different positions for their functional groups

Question 21

functional group isomers

Answer 21

molecules that have the same molecular formula but different types of functional groups

Question 22

amine

Answer 22

when the hydrogen of an alkane is substituted for an amino functional group (NH2)

Question 23

how are amines named as a suffix

Answer 23

parent hydrocarbon name - the end e, which is replaced with “amine”, number the carbon which the amine is on placing it between two dashes e.g pentan - 2 - amine

Question 24

primary amine

Answer 24

NH2 is connected to the first carbon

Question 25

what functional groups contain a carbonyl

Answer 25

aldehyde, ketone, carboxylic acid, ester and amide

Question 26

chemical formula ketone

Answer 26

Cn H2n O

Question 27

chemical formula aldehyde

Answer 27

Cn H2n O

Question 28

aldehyde functional group placement/formula

Answer 28

on the end of the carbon chain RC=OH, where R is either a hydrogen or an alkyl group

Question 29

aldehyde naming

Answer 29

replacing the 'e' on the end of the parent alkane with 'al'

Question 30

ketone functional group placement/formula

Answer 30

R-C=O-R', the carbonyl group is located within the chain, R and R' may or may not be the same and represent 2 alkyl groups

Question 31

naming ketone

Answer 31

replacing the final 'e' of the alkane with 'one', the location of the carbonyl is stated before this, e.g. pentan-2-one

Question 32

amides functional group

Answer 32

R-C=O-NH2, the carbonyl group is bonded to amide functional group and the first carbon on carbon chain

Question 33

what is used to increase the speed of a condensation esterification reaction

Answer 33

a catalsyst, sulfuric acid, H2SO4 in its liquid form

Question 34

when naming complex molecules, what three rules should always be abided by

Answer 34

the highest priority functional group always gets the lowest possible number, the functional group with the highest priority gets the suffic, the other functional groups use their alternative names and form the prefix of the name