Reactions

Question 1

How can ethene be made into an alkane?

Answer 1

Hydrogenation (+H2) and a nickel catalyst with a temperature of about 150 degrees.
MARGARINE

Question 2

How can an alkane be made into a halogenoalkane?

Answer 2

Free radical substitution
Add bromine under the presence of UV light.
Inititation 
Propagation 
Termination

Question 3

What is a double bond made up of?

Answer 3

A sigma bond and a pi bond
A sigma bond is formed when two s orbitals overlap.
A pi bond is formed when two p orbitals overap

Question 4

How do you test for C=C double bonds?

Answer 4

Add orange bromine water- solution decolourises

Question 5

Explain the process of electrophillic addition.

Answer 5

Double bond repels electrons in Br2- polarising Br-Br.
Heterolytic fission of Br2- gives up bonding electrons to the other Br and sticks to C.
Carbocation intermediate- Br- goes over.

Question 6

How is ethanol manufactured by steam hydration?

Answer 6

Ethene can by hydrated by steam at 300 degreeswith phosphoric (V) acid catalyst.

Question 7

How is ethanol made by fermentation?

Answer 7

Exothermic process carried out by yeast in anaerobic conditions.
C6H12O6 -> 2C2H5OH + 2CO2

Question 8

How can alkenes be formed from alcohols?

Answer 8

Dehydration.

Ethanol is mixed with acid catalyst (conc H2SO4) and heated to 170 degrees.

Question 9

How do you produce an ester?

Answer 9

Reacting a carboxylic acid with ethanol + a strong acid catalyst.
The OH bond is broken.

Question 10

What is the functional group for aldehydes and ketones?

Answer 10

C = O

Question 11

Name an oxidising agent.

Answer 11

Acidified potassium dichromate

Question 12

What are CFCs?

Answer 12

Chloroflourocarbons.

They contain only chlorine, flourine and carbon

Question 13

How can halogenoalkanes be made into alcohols?

Answer 13

Being hydrolysed with warm sodium hydroxide.

Question 14

What is the steps to nucleophillic substitution?

Answer 14

Nucleophile which provides a pair of electrons
The Cr-Br bond breaks heterolytically- both electrons from the bond are taken by Br-.
Br- falls off as the OH- bonds to the carbon.

Question 15

What can you use to compare reaction rates of halogenoalkanes.

Answer 15

Silver nitrate precipitation reaction

Question 16

What is the reaction for the breakdown of ozone?

Answer 16

R. + O3 -> RO. + O2

RO. + O -> R + O2

Question 17

How do you convert a straight chained alkane into a cyclical alkane?

Answer 17

Reforming

Remove a hydrogen molecule

Question 18

Outline how a catalytic converter decreases carbon monoxide and nitrogen monoxide emissions from internal combustion engines.

Answer 18

i) adsorption of CO and NO to the catalyst surface
ii) chemical reaction
iii) desorption of CO2 and NO2 from the catalyst surface.