The word alcohol, like the word acid, is the name for a large group of compounds. Alcohols are organic molecules that share certain chemical properties. The word organic refers to compounds based around the element carbon that are usually produced by living organisms. Chemical names ending in -ol are usually alcohols of some sort e.g. ethanol, propanol, paracetamol & cholesterol.
The simplest alcohol is methanol (CH3OH), pictured above. Ethanol, the alcohol found in alcoholic drinks, has the formula C2H5OH. It is the presence of that final -OH (hydroxyl group) that helps us to identify the molecule as an alcohol. Ethanol is produced by yeast during anaerobic respiration (fermentation). It is quite poisonous so it tends to limit the growth of the yeast once a certain concentration of ethanol has been reached. Part of the reason that ethanol is harmful to humans is that it is metabolised in the liver to form acetic acid which is thought to damage DNA within the cells. Ethanol also has an intoxicating effect which can lead to loss of inhibitions and an increased risk of injury due to reduced coordination. The following short video illustrates the point nicely.
.
Questions…
- What two products would you expect to be produced when methanol is completely oxidised?
- Name an organic acid.
- Name an inorganic acid.
- What would you expect the chemical formula of propanol to be?
Comments