Organic Chemistry Flashcards
What are fractions?
Mixtures of hydrocarbons with similar boiling points, separated by fractional distillation.
What is distillation?
A process used to separate mixtures.
What are the types of distillation?
Simple distillation - Separating out a liquid from a solution. Fractional distillation - Separating out a mixture of liquids.
What is a mixture?
Two or more substances not chemically bonded together.
What is a hydrocarbon?
A compound made up of only hydrogen and carbon atoms.
What is a homologous series?
A series of compounds that have the same general formula and the same properties. They differ by one CH2 group. (e.g. Alkanes)
What are alkanes?
A homologous series of hydrocarbons with the general formula of CnH2n+2, and only have single bonds.
Define saturated (in relation to hydrocarbons).
Containing only single bonds (maximum number of hydrogens bound to the carbon)
Define molecular formula.
Formula that shows the number of each type of atom within a compound. (e.g. C2H6)
What are alkenes?
Hydrocarbons with the general formula CnH2n and they contain a carbon to carbon double bond.
Are alkenes saturated?
No, as they have a double bond.
What is the prefix of the first five hydrocarbons?
Meth, Eth, Prop, But, Pent
What happens when you add bromine water to an alkene and alkane?
What is the reaction between an alkene/alkane and bromine water called?
Addition Reaction
What state are the hydrocarbons in when they enter the distillation collumn?
Gas
What ensures there can be fractional distallation in the column?
Temperature Gradient
What happens to the gas hydrocarbons when they hit a surface which is lower than their boiling point?
Condensation
Name the properties of long hydrocarbons
High boiling points, viscous, darker in colour, not very volatile
Where do long hydrocarbons condense in a distillation collumn?
Lower down the column
Learn the different fractions of the fractionating column
What part of the fractioning column stop condensed hydrocarbons running back down the column and provides the surface for condensation?
Bubble Caps
What is the range of carbons in the hydrocarbon chain found in the fractionating column?
~3 - 70+
Name a use of the refinery gases
Bottled gas/heating
Name a use for gasoline
Fuel for cars
Name a use for Naphtha
Starting material for chemical production of paints, explosive etc.
Name a use for kerosene(paraffin)
Jet engines, paint solvent
Name a use for diesel
Fuel for diesel engines
Name a use for fuel oil
Domestic central heating
Name a use for bitumen
Road surfacing and asphalt for roofs
What is cracking?
The process of breaking large hydrocarbons down into smipler molecules by heating them
What are the properties of small hydrocarbons?
Low boiling points, very volatile (ignite easily), flows easily
What are the products of cracking?
Smaller alkanes, and alkenes
What conditions are needed for cracking?
600-700oC, and an aluminium oxide (alumina) + silicon dioxide catalyst
What is the difference between the molecular and structural formula?
Molecular formula: Type and number of atoms in the molecule
Structural formula: Arragements of the atoms within the molecules
What is an isomer?
Compounds with the same molecular formulae but different structural formulae
Give an example of cracking
Dodecane –> Octane + Ethene
C12H26 –> C8H18 + 2C2H4
What happens to the boiling point of isomers when branching occurs?
What process turns vegetable oil into olive spread?
Hydrogenation
What does the process of hydrogenation entail?
Turning the liquid vegetable oil into solid spread
(Unsaturated fatty acids to saturated fats)
What type of cumbustion occurs when there is plenty of oxygen?
Complete combustion
Alkane + Oxygen –> Cardon Dioxide + Water
What reaction occurs when there is not enough oxygen for combustion?
Incomplete combustion
alkane + oxygen –> carbon + carbon monoxide + water
What is required to make an alkane react with halogens?
UV light
