Alcohols Flashcards
What is the general formula of an alcohol?
CnH2n+1OH.
What is an alcohol with 2 carbons formula?
C2H5OH.
What do all alcohols contain?
The same -OH functional group.
What is a homologous series?
A group of chemicals that react in a similar way because they have the same functional group - Alcohols.
What are the first three alcohols in the homologous series?
- Methanol.
- Ethanol.
- Propanol.
What is the formula and diagram for methanol?
CH3OH.
H
|
H--C--O--H
|
HWhat is the formula and diagram for ethanol?
C2H5OH.
H H
| |
H--C--C--O--H
| |
H HWhat is the formula and diagram for propanol?
C3H7OH.
H H H
| | |
H--C--C--C--O--H
| | |
H H HWhat do the first three alcohols have?
Similar properties.
What are alcohols?
Flammable.
What do alcohols produce when they burn in air?
- Carbon dioxide.
- Water.
What are the properties of the first three alcohols?
- They all dissolve completely in water to form neutral solutions.
- They all react with sodium to give hydrogen and alkoxides.
What is the main alcohol in alcoholic drinks?
Ethanol.
Why is ethanol used in alcoholic drinks over the other alcohols?
As it is not as toxic as methanol (which causes blindness if drunk), but it still damages the brain and liver.
What are alcohols used as?
- Solvents.
- Fuels.
Why are alcohols used as solvents?
They can dissolve most compounds that water can dissolve, and they can also dissolve substances that water can’t dissolve (e.g. hydrocarbons, oils and fats).
What is ethanol the solvent in?
- Perfumes.
- Aftershave lotions.
What does ethanol with chemicals added make?
Methylated spirit (meths)
Why is ethanol the solvent in perfumes and aftershave lotions?
As it can mix with both the oils and the water.
What are the uses of methylated spirit?
- Clean paint brushes.
- Fuel.
What is methylated spirit to humans?
Poisonous to drink.
How do we avoid drinking the poisonous methylated spirit by mistake?
A purply-blue dye is added.
What is ethanol used as?
A fuel in spirit burners.
Why is ethanol used as a fuel in spirit burners?
It burns fairly cleanly, without a smell.
What else can we do with ethanol?
Mix it with petrol and use it as a fuel for cars.
Why do we mix ethanol with petrol to use it as a fuel in cars?
Since pure ethanol is clean burning, the more ethanol in a petrol/ethanol mix, the less pollution produced.
How do some countries that don’t have oil deposits produce ethanol?
If they have plenty of land and sunshine, they can grow lots of sugarcane to ferment to form ethanol.
What is an advantage of fermentation to produce ethanol?
Sugar cane is a renewable source.
What does ethanol give when it reacts with sodium?
- Sodium ethoxide (2C2H5ONa)
- Hydrogen (H2).
