Organic Chemistry Flashcards
What is an organic compound?
Something that contains carbon atoms
How did crude oil form?
From the remains of dead animals and plants millions of years ago
What is crude oil a mixture of?
Hydrocarbons
What is a hydrocarbon?
Molecules made up of hydrogen and carbon atoms only
What is an alkane?
A saturated hydrocarbon
What is the general formula for an alkane?
CnH2n+2
What is a saturated hydrocarbon?
Contains only single covalent bonds between atoms
What is displayed formula?
Represents the covalent bonds present in a molecule as it lines
How do we name alkanes?
Look at the carbon chain length, apply the right prefix and add ‘ane’ on the end
What is the prefix for one carbon?
Meth-
What is the prefix for two carbons?
Eth-
What is the prefix for three carbons?
Prop-
What is the prefix for four carbons?
But-
How are the hydrocarbons in crude oil separated?
Fractional distillation
What is a fractional distillation ‘fraction’
Contains molecules with a similar number of carbon atoms
Describe temperature changes in the fractional distillation column
Hotter at the bottom, colder at the top
Why do the different fractions condense at different temperatures?
Different chain lengths have different boiling points
What are the two physical changes involved in fractional distillation?
Evaporation and condensation
What can crude oil fractions be used for?
Fuels as a raw material for the petrochemical industry
What different fuels come from crude oil?
Petrol, diesel, kerosene, heavy fuel oil, petroleum gases
What substances are made from crude oil, other than fuels?
Solvents, lubricants, polymers, detergents
What properties are affected by hydrocarbon chain length?
Boiling point, viscosity, flammability
How does hydrocarbon chain length affect boiling point?
The longer the chain, the higher the boiling point
What is flammability?
How easily a substance ignites or burns
How does hydrocarbon chain length affect the flammability?
The longer the chain, the less flammable it is
What is viscosity?
How thick a liquid is
How does hydrocarbon chain length affect viscosity?
The longer the chain length, the more vicious it is
Why do we burn hydrocarbon fuels?
To release energy
What type of reaction is combustion?
Oxidation
What are the two products when a hydrocarbon undergoes complete combustion?
Carbon dioxide, water
What is cracking?
Breaking down large hydrocarbons to smaller, more useful molecules
Why are smaller hydrocarbons more useful than larger molecules?
Make better fuels
What are the two types of cracking?
Catalytic cracking, steam cracking
What conditions are needed for catalytic cracking?
Vapour passed over a hot catalyst at high temperature
What conditions are needed for steam cracking?
Mix vapours with steam at high temperature
What are the products of cracking?
Alkane(s) and alkene(s)
What is an alkene?
An unsaturated hydrocarbon with a carbon-carbon double bond
What is the test for an alkene?
Turns bromine water from orange to colourless
What are alkenes used for?
Producing polymers and other chemicals
How do we name alkenes?
Look at the carbon chain length, apply the right prefix and add ‘ene’ on the end
What does the functional group on a molecule determine?
How it reacts
What functional group do alkenes contain?
Carbon-carbon double bond
What is a homogolous series?
A series of compounds with the same functional group
What causes incomplete combustion?
A lack of oxygen
What are the products of incomplete combustion?
Carbon monoxide, soot, water
What is an addition reaction?
A reaction hat adds a molecule across the carbon-carbon double bond
What conditions are needed for the addition of hydrogen to alkenes?
A heated catalyst of nickel at 300 degrees Celsius
What is produced when an alkene reacts with hydrogen?
A saturated hydrocarbon
What conditions are needed for the addition of water to alkenes?
React with steam passed over a catalyst of hot phosphoric acid
What is the product when an alkene reacts with water?
Ethanol
What functional group do alcohols contain?
-OH
What are the main uses of alcohol?
Fuels and solvent, making alcoholic drinks and bread
How do we name alcohols?
Look at the carbon chain length and apply the right prefix and add ‘anol’ on the end
What are two ways alcohols can be produced?
Fermentation and hydration of ethene
What conditions are needed for the fermentation of sugar?
Add sugar to yeast at 25-40 degrees Celsius in anaerobic conditions
What are the products of the fermentation of glucose?
Ethanol and carbon dioxide
What is produced when an alcohol reacts with oxygen?
Carbon dioxide and water
What gas is produced when an alcohol reacts with sodium?
Hydrogen
What is formed when alcohols react with an oxidising agent?
A carboxylic acid and water
What is formed when alcohol is dissolved in water?
A neutral solution
What functional group do carboxylic acids contain?
-COOH
How do we name carboxylic acids?
Look at the carbon chain length, apply the right prefix and add ‘anoic’ on the end
What is formed when a carboxylic acid dissolves in water?
An acidic solution
Why do carboxylic acids form weak acids in solution?
They are only partially ionised in water
What is produced when a carboxylic acid reacts with a metal?
A salt and hydrogen
What is produced when carboxylic acids react with carbonate?
Salt, carbon dioxide, water
What is produced in a reaction between carboxylic and alcohols?
An ester and water
What ester is produced in the reaction between ethanoic acid and ethanol?
Ethyl ethanoate
What is a monomer?
A molecule that can be bonded to other identical molecules to form a polymer
What is a polymer?
A long chain molecule made from many monomers
What is addition polymerisation?
A reaction that joins many monomers together to form a polymer
Why can alkenes be used in addition polymerisation?
They contain a double bond
How are polymers represented?
The displayed formulae are written as repeating units with a square bracket at each end, with an n outside the bracket
What is condensation polymerisation?
When monomers with different functional groups react to produce a new functional group plus a small molecule
How is the polymer structure represented after a condensation reaction?
-[[X][Y]]-
What functional groups do amino acids contain?
H2N, COOH
What polymer is formed from amino acids?
Proteins
What is DNA?
A naturally occurring polymer essential for life
What is the function of DNA?
Encodes genetic instructions for the development and functioning of living organisms and viruses
What is the structure of DNA?
Two polymer chains, made from four different monomers called nucleotides, in a double helix
What are other examples of naturally occurring polymers?
Proteins, starch, cellulose
What polymers are formed from glucose monomers?
Starch and cellulose