C13- halogenoalkanes

Question 1

what us a halogenoalkane

Answer 1

a saturated hydrocarbon containing one or more halogen

Question 2

name two uses of halogenoalkanes

Answer 2

solvents and pharmaceuticals

Question 3

what happens to the polarity of the C - X bond down group 7

Answer 3

it decreases

Question 4

what dies the letter X represent

Answer 4

a halogen atom

Question 5

what intermolecular forces are between halogenoalkane molecules?

Answer 5

van der waals forces
permenant dipole-dipole interactions

Question 6

whats permenant dipole dipole interactions

Answer 6

Polar molecules display attractions between the oppositely charged ends of the molecules.

Question 7

what solvents are halogenoalkanes soluble in?

Answer 7

organic solvents

Question 8

are halogenoalkanes soluble in water

Answer 8

no

Question 9

what mechanism is used to make halogenoalkanes

Answer 9

free-radical substitution

Question 10

what is a substitution reaction

Answer 10

where one functional group is replaced by another

Question 11

what are the stages of free-radical substitution?

Answer 11

initiation
propagation
termination

Question 12

what is a free radical

Answer 12

a species with an unpaired electron

Question 13

what is a homolytic fission

Answer 13

the breaking of a covalent bond to form two radicals

Question 14

what is a CFC

Answer 14

chlorofluoroalkanes

Question 15

what has caused the destruction of the ozone layer

Answer 15

chlorine radicals

Question 16

what is used instead of CFCs to protext the ozone layer?

Answer 16

HFCs (hydrofluorocarbon)

Question 17

what is a nucleophile

Answer 17

an electron pair donor

Question 18

nake three nucleophiles

Answer 18

hydroxide
cyanide
ammonia

Question 19

what us represented by a curly arrow?

Answer 19

the movement of an electron pair

Question 20

where can a curly arrow begin?

Answer 20

at a lone pair or the centre of a bond

Question 21

what is a leaving group?

Answer 21

the group that is lost in nucleophilic substitution

Question 22

what conditions are required for nucleophilic substitution of hydroxide?

Answer 22

dissolve halogenoalkanes in ethanol, aqeuous NaOH and reflux

Question 23

what is hydrolysis

Answer 23

the breaking of chemical bonds with water/hydroxide ions

Question 24

rate of nucleophilic substitution of halogenoalkanes

Answer 24

stronger the C-X bond the slower the rate

Question 25

what happens tk the strength of the C-X bond down geoup 7?

Answer 25

it decreases

Question 26

what is a hydrogen ion

Answer 26

a proton

Question 27

what conditions are required for nucleophilic substitution of cyanide

Answer 27

dissolve halogenoalkane in ethanol, aqueous KCN and reflux

Question 28

what conditions are required for nucleophilic substitution of ammonia

Answer 28

dissolve halogenoalkane in ethanol, concentrated ammonia in excess and reflux

Question 29

what is the 2nd ammonia used for

Answer 29

acts as a base to remove a hydrogen ion

Question 30

what is a: 1) primary amine 2) secondary amine 3) tertiary amine

Answer 30

1) RNH2 H | H - N - X | R 2) R2NH H as amine goes from prim/sec | /tert, thats how much R is R - N - X attached to the N, which | affects amount of H in bond. R 3) R3N R | R - N - X | R

Question 31

what is an elimination reaction

Answer 31

a reaction where a small group is removed

Question 32

what is the solvent in an ethanoic solution

Answer 32

ethanol

Question 33

how does hydroxide behave in an erhanoic solution

Answer 33

as a base

Question 34

what is a base

Answer 34

a proton acceptor

Question 35

what mechanism is most likely for a tertiary halogenoalkne

Answer 35

elimination

Question 36

what mechanism is more likely for a primary halogenoalkane

Answer 36

nucleophilic substitution

Question 37

nucleophilic reaction

Answer 37

a class of reactions in which an electron rich nucleophile attacks a positively charged electrophile to replace a leaving group