The term "acid" will sometimes inevitably conjure up the image of a destructive substance that cannot possibly serve any beneficial purpose. On the other hand, basic substances are sometimes thought of a foreign scientific term. These perceptions could not be further from the truth. Scientifically, acids and bases are differentiated by the hydrogen ion concentration. Acids add to the number of hydrogen ions and bases lower it. These characteristic properties have ensured that a number of acids and bases have widespread applications.
Vinegar (acetic acid) and lemon juice (citric acid) are integral fixtures of almost every kitchen. Boric acid acts as an antiseptic and cleaner because it has weak acidic properties. Citric acid also produces low-pH shampoos and toothpastes. Among the bases, sodium bicarbonate (baking soda) is used in a number of different circumstances. The combination of baking soda with a weak acid results in the production of carbon dioxide, thus causing dough and batter to rise. Sodium hydroxide (caustic soda) is used to a great extent in oven cleaners and drain cleaners because of its ability to convert fats to water-soluble soap.
Ironically, citric acid plays a key role in the production of antacid, a famous stomach remedy. Aluminium hydroxide is a base included in the production of antacids. Magnesium sulphate, also known as Epsom salts, provides a powerful laxative and eliminates poisonous substances from the body. Aluminium hydroxychloride works as an antiperspirant.
Nitric acid is one of the main ingredients of TNT. Sulphuric acid is a significant component of car batteries and is ideal in the production of fertilisers. A base called aluminium hydroxide applies to water purification, dyeing of garments and the production of some varieties of glass. A useful property of baking soda (sodium bicarbonate) is the obstruction of the flow of oxygen to a flame, which assists in firefighting.