C7 Alkanes,alcohols,carboxylic Acids, Esters Flashcards
What sort of bonds do alkanes have?
They have single covalent bonds- they are saturated
What are alkanes made from?
-They are made up of chains if carbon atoms surrounded by hydrogen atoms.
What is the formula for all alkanes?
CnH2n+2
What is the names of the first two alkanes and what is their molecular formula?
Methane Ethane
CH4 C2H6
What do alkanes burn to give?
Alkanes burn to produce carbon dioxide and water.
Alkane+oxygen—> carbon dioxide + water.
What do alkanes not react with and why?
Alkanes are pretty unreactive to most chemicals.
They don’t react with aqueous agents
Alkanes don’t react because the C-C bonds and the C-H are difficult to break.
What is the functional group of alcohols?
‘OH’
Describe if the following are soluble in water, good solvents, billing points and at room temperature:
- ethanol
- alkanes
- water
ETHANOL- Soluble in water, good solvent, a boiling point of 78 C, liquid at room temperature but volatile.
ALKANE- insoluble in water, bad solvent, boiling point of -103 (for ethane), gas at room temp.
WATER, good solvent, boiling point of 100 degrees and is a liquid at room temp but is not volatile.
Why are alcohols so good manufacturing?
Can dissolve lots of compounds that water can’t like hydrocarbons and oil, makes it a very useful solvent.
Describe all the uses for ethanol.
- Ethanol is used in perfumes and aftershave lotions.
- ‘methylated spirit’ is ethanol with chemicals added to it, to clean paint brushes and as fuel.
Give the reaction for ethanol reacting with sodium and also water reacting with sodium.
Sodium+ethanol—> sodium ethoxide+hydrogen
Sodium+water—> sodium hydroxide+hydrogen
What is the functional group of Carboxylic acids?
‘-COOH’
What does carboxylic acid react with?
Carboxylic acids are like other acids, they react with alkalis,carbonates and reactive metals.
When carboxylic acids react with alkalis,metals or carbonates what do they form?
Salts that end in ‘anoate’
Like methanoic acid forms a methanoate
What do carboxylic acids make when reacted with the following?
1) an alkali
2) a metal
3) a carbonate
1) give salt and hydrogen
2) give salt and water
3) give a salt,water and carbon dioxide.
What happens if beer is left out in the air?
The ethanol will be oxidised to ethanoic acid,which stink, and will make the beer taste rancid.
What is the function group of esters?
‘-COO’
How are esters formed?
They are formed from an alcohol and a carboxylic acid. It’s called an esterification reaction.
To start the reaction you need a strong acid catalyst( like sulfuric acid)
Why are esters very good for the industry?
1) Esters have pleasant smells, often quite sweet and fruity.
2) they are volatile, makes them ideal for perfumes.
3) they are good plasticisers
4) used as solvents - paint and nail varnish.
What are fatty acids?
They are carboxylic acids with long chains.
What is a glycerol?
An alcohol. NOTICE THE ‘OL’ DIPSHIT?
Fatty acids and glycerols combine to make what?
To make fats and oils?
Saturated=
- Single bonds
- solid at room temp
Unsaturated=
Double bonds.
- liquid at room temp
What are the properties of animal fats?
They are saturated- solid at room temp
What are the properties of vegetable oils?
They have mainly unsaturated hydrocarbon chains
- liquid at room temp.
What do the names of carboxylic acids end in?
‘anoic’ acid
