INTRODUCTION TO CHEMISTRY
Chemistry may be defined as the science that is concerned with the composition and the structure of matter, and with the forces that hold the structures together. Chemistry as a science has, as its primary objectives, the determination of the nature and properties of the non-living matter, which surrounds us, and the preparation of new substances that are scientifically interesting, or generally useful from the materials which nature has provided. In trying to determine the nature of substances, it probes into principles governing the changes that matter undergoes, when subjected to conditions which they normally do not encounter, such as high temperature, high pressure, contact with other materials under different conditions, etc.
The focus of chemistry, however, is probably on the chemical reaction. The interest of chemistry extends to every conceivable aspect of these transformations engendered by chemical reactions, and includes such considerations as – detailed descriptions of how and at what rate, reactions proceed, the conditions required to bring about desired changes, and to prevent undesired changes, the synthesis of substances that occur in nature and those that have no natural counterparts and the quantitative mass relations between the materials involved in chemical changes.
The three main branches of chemistry are: physical, inorganic and organic. There are in addition, other branches, such as biochemistry which deals with the effects of chemicals on living cells, medicinal chemistry which deals with the physiologically active compounds such as aspirin, chloroquine and so on, industrial chemistry, which considers the applications of chemistry in industries and environmental chemistry which investigates the possible adverse effects of chemistry on the environment.
The study of chemistry helps us acquire knowledge about matter. Being an experimental science, we perform experiments, learn to observe, record and make intelligent inferences. Chemistry has contributed greatly towards providing our basic needs and improving the quality of our life.
Lastly, the study of Chemistry is designed to introduce learners to the basic ideas of the subject, how these ideas help to explain the materials in our world, and how they can be changed.
CHEMISTRY IN OUR LIFE
There are lots of chemical changes around us all the time. These include:
- Lighting a match.
- Burning fire wood.
- Rusting nails.
- Rotten leaves.
- Making of palm.
- Manufacturing of drugs, etc.
All the things we use every day such as:
- Soaps and detergents.
- Hair cream and perfumes.
- Oil and margarine.
- Plastics made through chemical processes.
Chemistry, and other fields of science, have developed through a series of discoveries. They use their senses to observe what is happening around them. Through observation, they see a certain pattern which often leads to a problem they try to solve. They put forward a reasonable explanation called hypothesis and carry out appropriate experiments to test it. They then carefully record their observations and the results of their experiments.
If the experiments support the hypothesis, they carry out further investigations. When a hypothesis has been tested and found to be correct within the limits of available evidence, it becomes a theory. A scientific law or principle is established only after the theory has been extensively tested and proven true without any exception.
If the experiments give negative results, then the scientist goes back to his or her hypothesis and either modifies it or puts forward a new hypothesis. This way of studying a problem is known as the scientific method and it is the foundation of all scientific research.
USES OF CHEMISTRY
The study or knowledge of Chemistry has contributed greatly towards providing our basic needs and improving the quality of our life. These include:
- FOOD: The use of fertilisers, insecticides and pesticides has helped to increase food production. Chemical processes are designed to preserve and store food for a long period of time; so that it can be exported and made available to more people.
- CLOTHING: Through intensive chemical research, manmade textile fibres are produced. These have made available, a wide range of clothing materials for man’s use.
- MILITARY: The duty of the military is to defend the territorial integrity of a nation or state. The military cannot do this without ammunition. Chemistry has contributed to the discovery and description of the behaviour of chemical substances such as explosives used by the military. The gunpowder used by the earliest guns was made by mixing sulphur, charcoal and potassium trioxonitrates (V).
- SPACE SCIENCE: In our efforts to gain more knowledge of the other planets and outer space around us, special rockets called space-rockets are sent into space. The first space rocket was sent into space on October 4, 1957 by Russia. In July, 1969, Apolio II Astronauts Neil Armstrong and Edwin Aldrin landed on the moon. These were made possible by science and technology.
- HOUSING: To overcome the present need for housing and maximise use of land space especially in cities, many high-rise buildings are being constructed. These buildings need materials like cement, concrete, steel, bricks and tiles which are produced by chemical industries.
- MEDICINE: Health is wealth. The health life that many people enjoy is due to the variety of medicines that are available as a result of chemical research and technology.
- TRANSPORTATION: Modern transportation system is an essential feature of today’s world. This rapid development from carts pulled by animals to the latest air craft was made possible by chemicals producing suitable fuels and structural materials like alloys, which are light, strong and heat resistant.
ADVERSE EFFECTS OF CHEMISTRY
Chemical processes and products also have negative or adverse effects on our daily life.
1) Corrosion of Iron
Corrosion or rusting of iron occurs when iron is exposed to water and air (oxygen). Corrosion can be regarded as the slow deterioration of iron to iron (III) oxide:
Rusting can be prevented by:
- Application of protective coating.
- Application of sacrificial metal.
- Cathodic protection.
- Oiling and greasing.
One of the main adverse effects of chemical industries is the pollution of our as environment by:
- Chemical wastes from factories and oil refineries.
- Radioactive wastes from nuclear plants.
- Oil spillage, exhaust from motor vehicles.
Pesticides, fertilisers and acid rain have made our environments unclean and endangered plants and animals life. Human health is also threatened by environmental pollution.
3) Drug Abuse
Drug abuse and drug addiction is a major problem in our society, especially among the youth. Drugs that are abuse are heroin, cocaine and morphine. These drugs are not used for medical treatment, rather they are additive and some bad people in the society produce and sell them to make huge profit. Many countries have imposed strict laws to control pollution and drug abuse; but the most effective control measure is education.
CAREERS USING CHEMISTRY
Have you thought of what you want to do when you leave school?
Chemistry opens door to many careers. It is sometimes called ‘the central science’, because it lies between Biology and Physics. So if you would like to study these further, Chemistry is a great help.
But hopefully you will want to learn more about Chemistry because you enjoy it!
Here are some careers where further studies in Chemistry will be an advantage, if not a requirement:
- Agricultural Scientist.
- Animal technician.
- Art restorer.
- Chemical engineer.
- Civil engineer.
- Civil Service Science Officer.
- Cosmetics scientist.
- Dental technician.
- Electrical engineer.
- Environmental Health Officer.
- Food scientist.
- Forensic scientist.
- Information Scientist.
- Journalist (science).
- Laboratory technician.
- Lecturer in science.
- Manager in an industry.
- Marine scientist.
- Materials Scientist.
- Medical technician.
- Patent lawyer.
- Personnel manager.
- Pollution controller.
- Production manager.
- Quality controller.
- Research Scientist.
- Safety officer.
- Sales person.
- Scientific archaeologist.
- Sports Scientist.
- Teacher of science.
- Technical support staff.
- Technical writer.
- Veterinary surgeon/assistant.
- Waste disposal manager/scientist Water technologist Wine taster Zoologist.