When we think of alcohol, the first thing that comes to our mind is drink… However, alcohol has better uses and is more than just a drink. Let us find out more about this important thing.
How is alcohol made?
Whether it is made as wine or beer, the method of production is essentially the same. A carbohydrate, such as starch or sugar, is broken down into glucose form and is then mixed with yeast and allowed to ferment for weeks or even months. Catalysts within the yeast then convert the glucose into alcohol and carbon dioxide thereby releasing the energy that the yeast needs in order to survive and grow.
Uses of Some Alcohols
Alcohols are not just drinks but are widely used as solvents. This is because of its ability to dissolve many substances that cannot be dissolved in water. Ethanediol (ethylene glycol), an alcohol, is used as anti-freeze, to prevent water from freezing in car radiators. The sweet tasting glycerol (glycerine) is an alcohol which is made as a by-product of the manufacture of soap from fats or oils. Ethanol has a boiling point which is similar to that of petrol. It burns very well with a clean flame, and can therefore be used as a fuel.
Oxidation of Alcohols
Alcohols react with organic acids to form substances called as esters, which are found in all living organisms. Animal fats and vegetable oils are examples of such esters. Many esters are sweet-smelling chemicals which are widely distributed among fruits. It is these that give a fruit its characteristic smell and flavour. Many esters are manufactured for use as food flavourings, while others are used as solvents. Ethyl ethanoate (also called as Ethyl acetate,the CAS No. is 141-78-6) for example is made from ethanol and ethanoic acid and is a common solvent for paints, glues and nail varnish.
Oxidation of alcohols to organic acids like vinegar is a two-stage process, the intermediate compound being an aldehyde. Methanol, for example, is oxidised to methanal (formaldehyde), and is used to preserve dead biological specimens and organs for use in scientific research. The oxidation of methanal produces methanoic (formic) acid, which is responsible for the stings of ants and nettles.