Chemicals

“Chemicals” represents a very broad category of substances and can not be defined in a single line. Generally chemicals can be defined as the substances that are either single elements or has been prepared by chemically reacting two or more elements. Chemicals have their certain chemical composition which is independent of place, time, pressure or temperature. For example, pure water is a chemical compound which displays same properties and same chemical composition (i.e. H2O) whether it is collected from sea, river, water tape, rain or prepared in chemistry lab. Chemicals should not be compared with mixtures as mixtures are homogeneous or heterogeneous mix of two or more chemicals.

Each of the chemicals has its own name and chemical representation (chemical formula). The chemicals formula of a compound provides information about what type of basic elements are present in that compound and in what ratio or structure. The chemicals are basically divided into two main categories:-

1. Elements: - Elements are the basic building blocks of all the substances that one can see in his whole lifespan. Elements are made of same type of atoms that can not be further broken down. There are approximately 120 elements known to the mankind.

2. Compounds: - Compounds are the chemicals that are prepared from two or more elements with the help of a chemical reaction. The number of compounds that can be prepared from these 120 elements is simply unbelievable. There are approximately 30 million compounds that have been prepared till now.

The chemicals can also be classified as organic or inorganic. The chemicals that have carbon as one of their constituents are called organic chemicals while all other chemicals are termed as inorganic chemicals.

The chemicals have become an integral part of our daily life and a life without chemicals is simply unconceivable. Cosmetics, pesticides, pharmaceuticals, insecticides, additives, preservatives, industrial chemicals and household chemicals are some of the popular classes of chemicals that are heavily used in day to day life. Apart from being so much advantageous, chemicals have also some disadvantages. For example, there are several chemicals such as alcoholic liquor, heroin and other intoxicants that are injurious to health. Chemicals are utmost important to smoothly run the engine of our life but the use of harmful chemicals should be avoided.