Organic Chemistry And Alkanes Flashcards
Halogenoalkanes are similar in structure to alkanes except at leat one h atom has been replaced with a halogen atom —- I.e. ….
They have the prefix …
Halogenoalkanes are similar in structure to alkanes except at leat one h atom has been replaced with a halogen atom —- I.e. F, Cl, Br or I.
They have the prefix fluoride-, chloro-, bromo- or iodo-.
What is a stereoisomer
What is a stereoisomer
A stereoisomer is one of two or more forms of a molecule having the same structural formula but a different arrangement in space
What is a Z-isomer?
What is a Z-isomer?
A Z-isomer is an isomer which has the higher priority groups both above or below the double bond
What is E–isomer?
What is E–isomer?
An E-isomer Is an isomer that has the higher priority groups across the double bond from each other
Use the CIP rules to decide which one has the higher priority:
a) CH3 or H
b) CH2 CH3 or Cl
c) CH2 CH2 CH3 or OH
d) CH2 CH2 CH2 CH2 COOH or CH2 CH2 CH2 CH2 CH2 OH
Use the CIP rules to decide which one has the higher priority:
a) CH3
b) Cl
c) OH
d) CH2 CH2 CH2 CH2 COOH
Order of priority of different functional groups (1=highest)
Order of priority of different functional groups (1=highest)
1- Other functional groups
2- alkenes
3- alkyl groups
4- halogens
What is petroleum
What is petroleum
A mixture of that consists mainly of Alcaine hydrocarbons
Why are alkanes described as saturated hydrocarbons
Why are alkanes described as saturated hydrocarbons
They only contain carbon and hydrogen atoms, and each of their carbon atoms forms 4 single bonds – there are no C=C double bonds present
What property is fractional distillation separated by?
What property is fractional distillation separated by?
Boiling point
What property is fractional distillation separated by?
Thermal cracking
high temperature up 1000°C and high pressure up to 70 atm
produces lots of alkanes that are used to make heaps of valuable products like polymers
Catalytic cracking
Uses a zeolite catalyst at a slight pressure and high temperature about 500°C
produces a romantic hydrocarbons and the alkanes needed to produce Motor fuels
cuts costs because the reaction can be done at a lower temperature and a lower pressure
the catalyst speed up the rate of reaction, saving time
What property is fractional distillation separated by?
Thermal cracking
Catalytic cracking
Give three pollutants produced by vehicle exhausts
Give three pollutants produced by vehicle exhausts
Nitrogen oxides
Unburnt hydrocarbons
Carbon monoxide
Explain how acid rain is caused by burning fossil fuels containing sulfur
Explain how acid rain is caused by burning fossil fuels containing sulfur
The sulfur burns to produce sulfur dioxide gas.
if sofa dioxide enters the atmosphere, it can dissolve in the moisture and form sulfuric acid
Describe one method for removing sulfur dioxide from flue gases
Describe one method for removing sulfur dioxide from flue gases
Powdered calcium carbonate can be mixed with water to make an alkaline slurry
When the flue gases mix with the alkaline slurry, the acidic sulfuric dioxide gas reacts with the calcium compounds to form a harmless salt calcium sulfate
Define the term stereoisomer
Define the term stereoisomer
A molecule that has the same structural formula as another molecule but its atoms are arranged differently in space
What are fractions
What are fractions
Mixture of hydrocarbons with the same boiling points
Explain how a fractionating column works in five key points
Explain how a fractionating column works in five key points
- Crude oil is passed into a fractionating column where it boils
- The column is hotter at the bottom then the top
- the vapour rises up the column until it condenses
- small hydrocarbons have weak van der Waal’s forces, hence low boiling points and condense near the top of the column
- large hydrocarbons have strong van der Waal’s forces, hence high boiling points and condense near the base of the column
Write a list of the fractions, in order of increasing boiling point, and give a use for each.
Write a list of the fractions, in order of increasing boiling point, and give a use for each.
Lovely People Never Kill Dogs Or Babies
Liquefied Petroleum gas LPG- gas for cooking
Naphtha - making chemicals
Kerosine - jet fuel
Diesel - fuel for lorries
lubricating Oil - waxes and polishes
fuel Oil - for ships
Bitumen- roads
Name the two types of cracking. State the conditions required for each and give one useful product of each process.
Name the two types of cracking. State the conditions required for each and give one useful product of each process.
thermal cracking:
high temperature
high pressure
makes alkenes
catalytic cracking: high temperature slight pressure zeolite catalyst makes motor fuels makes aromatic hydrocarbons
Why is cracking economically important?
Why is cracking economically important?
it converts hydrocarbons for which supply exceeds demand
into hydrocarbons for which demand exceeds supply
(a) Write an equation for the complete combustion of octane.
(b) Write two equations for the incomplete combustion of octane.
(c) Give two reasons why incomplete combustion is undesirable.
(a) Write an equation for the complete combustion of octane.
C8H18 + 12½O2 —> 8CO2 + 9H2O
(b) Write two equations for the incomplete combustion of octane.
C8H18 + 8½O2 —> 8CO + 9H2O
(c) Give two reasons why incomplete combustion is undesirable.
Less energy released, CO is a toxic gas, C particulates are carcinogenic
a)Identify five pollutants produced during the combustion of alkanes.
b) Explain why each is harmful.
c) Explain how two of these pollutants are removed from exhaust fumes. Write an equation to illustrate your answer.
a)Identify five pollutants produced during the combustion of alkanes.
CO2, CO, C, NO2 or NO, SO2, unburned hydrocarbons
b)Explain why each is harmful.
CO2 - greenhouse gas
CO - reduces ability of blood to carry oxygen
C - carcinogen (causes cancer)
NO2 or NO - cause acid rain/destruction of ozone layer
SO2 - acid rain
unburned hydrocarbons. - greenhouse gases/photochemical smog
c)Explain how two of these pollutants are removed from exhaust fumes. Write an equation to illustrate your answer
2CO + 2NO —> N2 + 2CO2
