u2 unknowns

Question 1

what is the type of reaction that occurs when a bromoalkane reacts with potassium hydroxide dissolved in ethanol?

Answer 1

elimination

Question 2

what is created when a monohaloalkane is reacted with alcoholic alkoxides?

Answer 2

ethers

Question 3

how are alkoxides formed?

Answer 3

by adding an alkali metal such as sodium or potassium, to an alcohol such as methanol or ethanol.

Question 4

example of the formation of alkoxides

sodium added to methanol forms…

Answer 4

sodium methoxide and hydrogen

Question 5

what is a methoxide ion capable of acting as?

Answer 5

a nucleophile

Question 6

formation of alcohols via monohaloalkane nucleophillic substitution

Answer 6

monohaloalkane undergoes nucleophilic substitution when refluxed with an alkali. The hydroxide ion from the alkali acts as a nucleophile and attacks the carbon attached to the halogen. A halide ion is formed as the two bonding electrons in the carbon-halogen bond then move on to the halogen atom.

Question 7

formation of nitriles

Answer 7

monohaloalkanes can undergo nucleophilic substitution reaction with ethanolic cyanide to form nitriles.
as a result of a reaction, the chain length increases by one carbon atom.

Question 8

what is formed when nitriles are hydrolysed?

Answer 8

carboxylic acid.

Question 9

formation of ethers

Answer 9

when a monohaloalkane is reacted with alcoholic alkoxides to form ethers.

Question 10

when 1 bromobutane is reacted with potassium methoxide, what is the name of the ether formed?

Answer 10

methoxybutane.

Question 11

what is required to eliminate a hydrogen halide from a monohaloalkane to form an alkene?

Answer 11

KOH dissolved in hot ethanol

hot ethanol must be used so that elimination is promoted over nucleophilic substitution.

Question 12

which reagent can be used to convert carboxylic acids into alkanals?

Answer 12

lithium aluminium hydride

Question 13

which base is the strongest?

C4H9NH2
NH3
C2H5NH2
CH3NH2

Answer 13

C4H9NH2

Question 14

state the conditions and reagents required for the nitration of benzene?

Answer 14

conc H2SO4 + conc HNO4 refluxed at 50 degrees

Question 15

requirements for bromination of benzene

Answer 15

AlBr3/Br2
or
FeBr3/Br2

Question 16

requirements of alkylation of benzene

Answer 16

R-Cl/AlCl3

Question 17

requirements of chlorination of benzene

Answer 17

AlCl3/Cl2
or
FeCl3/Cl2

Question 18

requirements for nitration of benzene

Answer 18

conc HNO3 and conc H2SO4

reflux @ 50°C

Question 19

requirements for sulfonation of benzene

Answer 19

conc H2SO4 reflux

Question 20

what is LiAl4?

Answer 20

lithium aluminium hydride
a STRONG reducing agent commonly used in organic reactions

therefore it is used to convert carboxylic acids to aldehydes or alcohols.

Question 21

what type of reaction does benzene take part in?

Answer 21

electrophillic SUBSTITUTION

Question 22

how does the strength of the magnetic field affect the energy difference between spin states in NMR?

Answer 22

the stronger the magnetic field, the greater the energy difference between them

Question 23

why does the chemical shift decrease as more hydrogens are attached?

Answer 23

the more hydrogens attached, the greater the shielding (as greater electron density) and the less the magnetic force will be felt, thus the smaller chemical shift.

Question 24

when an acid is diluted, what decreases?

Answer 24

H+ ion concentration

Question 25

what catalyst is used for the hydrolysis of a nitrile to form a carboxylic acid?

Answer 25

aqueous acid or strong base

Question 26

what catalyst is used for the hydrolysis of an amid to form a carboxylic acid?

Answer 26

aqueous acid or strong base