Why Do Some Acids Cause Burns?
Some acids burn because they have a strong tendency to absorb water, giving out a great deal of heat in the process. Since most living cells contain water the strong acids, such as sulphuric acid, hydrochloric acid and nitric acid, react with them and kill the cells, causing very serious burns. These three acids, as well as others such as perchloric acid and benzene sulphuric acid are called mineral acids because they are manufactured from minerals. They are all strong and dangerous acids. They have tremendous industrial value, but great care must be used in handling them.
Most organic acids-that is to say, those made from living things-are weak acids. Vinegar or lemon juice is an example. All acids taste sour and many attack metals, turning them into salts and releasing hydrogen. Special clothing is worn by men handling acids to protect them from serious burns. Acid must always be poured slowly into water, never water into acid. If you are burned by acid you should wash your skin with large quantities of water and then with a weak ammonia solution. If your eyes are affected, flush them immediately with lots of water and then with bicarbonate of soda solution, which neutralizes any acid left.
There are two main chemical groups of acids. They are organic and inorganic acids. Organic acids contain carbon while inorganic acids don’t. Some examples of inorganic acids are hydrochloric acid, nitric acid and sulphuric acid. Formic acid, acetic acid, etc are organic acids. They are weaker acids. Most of the organic acids are harmless. But inorganic acids can be dangerous as they can burn the skin.
How do acids burn the body?
Inorganic acids have a strong tendency to absorb water and release a lot of heat in the process. Since most of the living cells contain water, strong acids like hydrochloric, sulphuric and nitric acid react with them and kill the cells, causing severe burns.
Acids are also essential for the body. Our stomachs contain hydrochloric acid to digest food. The stomach lining protects us from the acid, if the lining breaks; the acid can burn and cause an ulcer. Amino acids are essential for all kinds of life. Eight special amino acids are needed to stay alive.
Acids also have tremendous industrial importance. Millions of tons of sulphuric acid is made every year and used for many industrial purposes. It dissolves rust and scale deposited on iron. Acids are also used in making fertilizers, pigments, dyes, plastics and synthetics. Aquaregia, which is a mixture of nitric and hydrochloric acid, is used to dissolve gold and platinum.