Chemistry is a branch of Science. Science is basically the study of living and non-living things. The branch of science that study living things is called Biology.
The branch of science that study non-living things is called Physical Science.
Physical Science is made up of:
- Physics- the study of matter in relation to energy
- Chemistry– the study of composition of matter.
Chemistry is thus defined as the branch of science that deals with the structure composition, properties and behavior of matter.
Basic Chemistry involves studying:
States/phases of matter
Matter is anything that has weight/mass and occupies space/volume. Naturally, there are basically three states of matter.
- Solid-e.g. soil, sand, copper metal, bucket, ice.
- Liquid e.g. water, Petrol, ethanol/alcohol, Mercury (liquid metal).
- Gas- e.g. Oxygen, Nitrogen, Water vapour.
A solid is made up of particles which are very closely packed. It thus has a definite/fixed shape and fixed/definite volume/occupies definite space. It has a very high density.
A liquid is made up of particles which have some degree of freedom. It thus has no definite/fixed shape. It takes the shape of the container it is put. A liquid has fixed/definite volume/occupies definite space. A gas is made up of particles free from each other. It thus has no definite/fixed shape. It takes the shape of the container it is put. It has no fixed/definite volume/occupies every space in a container.
Separation of mixture
A mixture is a combination of two or more substances that can be separated by physical means.
Simple methods of separating mixtures at basic chemistry level include
- Sorting/picking- this involve physically picking one pure substance from a mixture with another/other. e. g. sorting maize from maize beans mixture.
- Decantation– this involve pouring out a liquid from a solid that has settled/sinking solid in it. e. g. Decanting water form sand.
- Filtration– this involves sieving /passing particles of a mixture through a filter containing small holes that allow smaller particle to pass through but do not allow bigger particle to pass through.
- Skimming- this involve scooping floating particles. e.g. cream from milk
Metals and non-metals
Metals are shiny, ductile(able to form wires), malleable (able to form sheet) and coil without breaking. E.g. Iron, gold, silver, copper. Mercury is the only liquid metal known. Non-metals are dull, not ductile (do not form wires), not malleable (do not form sheet) and break on coiling/brittle. E.g. Charcoal, Sulphur, plastics.
Conductors and non-conductors
- A conductor is a solid that allow electric current to pass through.
- A non-conductor is a solid that do not allow electric current to pass through.
- All metals conduct electricity. All non-metals do not conduct electricity except carbon graphite.
Drugs
A drug is a natural or synthetic/man-made substance that when taken changes/alter the body functioning. A natural or synthetic/man-made substance that when taken changes/alter the abnormal body functioning to normal is called medicine. Medicines are thus drugs intended to correct abnormal body functions.. Medicines should therefore be taken on prescription and dosage.
A prescription is a medical instruction to patient/sick on the correct type of medicine to take and period/time between one in take to the other.
A dosage is the correct quantity of drug required to alter the abnormal body function back to normal. This is called treatment.
It is the professional work of qualified doctors/pharmacists to administer correct prescription and dosage of drugs/medicine to the sick.
Prescription and dosage of drugs/medicine to the sick use medical language.
Example
- 2 x 4; means “2” tablets for solid drugs/spoon full for liquid drugs taken “4” times for a duration of one day/24 hours and then repeated and continued until all the drug given is finished.
- 1 x 2; means “1” tablets for solid drugs/spoon full for liquid drugs taken “2” times for a duration of one day/24 hours and then repeated and continued until all the drug given is finished.
Some drugs need minimal prescription and thus are available without pharmacist/ doctor’s prescription.
They are called Over The Counter (OTC) drugs.
OTC drugs used to treat mild headaches, stomach upsets, common cold include:
- Painkillers
- Anti acids
- Cold/flu drugs.
All medicines require correct intake dosage. When a prescription dosage is not followed, this is called drug misuse/abuse.
Some drugs are used for other purposes other than that intended.
This is called drug abuse. Drug abuse is when a drug is intentionally used to alter the normal functioning of the body. The intentional abnormal function of the drug is to make the victim have false feeling of well-being. The victim lack both mental and physical coordination.
Some drugs that induce a false feeling of well-being are illegal. They include heroin, cocaine, bhang, mandrax and morphine. Some abused drugs which are not illegal include: miraa, alcohol, tobacco, sleeping pills.