Chemistry is a subject loaded with complex words and phrases. This might seem a little overwhelming. In fact, getting to grips with all the scientific vocabulary might be the thing that is putting you off opening your textbooks in the first place.
Luckily, with this handy guide to the most important general chemistry terms, you should start feeling more comfortable in no time. They are worth knowing not only for chemists themselves, or for the professors and engineers who use them. Rather, everyone should know these words and definitions, as they help to unlock that world of fizzing experiments, laboratories, and flaming reactions that is chemistry.
So, if you are studying for your GCSEs, or if you need a refresh before your A Level exams, take a look at this introductory chemistry dictionary and learn something!
If you reckon you know it all already, check out our other articles with everything you need to know about chemistry.
Let’s start small. Chemistry, basically, is the study of atoms, elements, compounds, and molecules. These are four terms to get you going. But what do they mean? It’s an important question, as these four things (and the stuff of which they themselves are made) make up everything in the universe.
An element – iron, say, or oxygen – is a pure substance or something that you cannot break down into another substance. You can only break it down into atoms, or the smallest bits of the element that you can still recognise as this or that element. An element is only lots of the same atom.
How about molecules and compounds? These are slightly different.
If you’re interested, we’ve also published a piece on wicked chemistry facts. Check it out!
To understand how these atoms bond together, we need to go smaller still. As you may know from your chemistry lessons, atoms are made of particles, which either clump in the atom’s nucleus or spin around that nucleus. These particles have a charge that is either positive, neutral, or negative. The nucleus (the centre of the atom) holds the protons, which have a positive charge, and the neutrons, which are neutral. The negatively-charged electrons, meanwhile, orbit the nucleus.
These are key to understanding how molecules and compounds are made. Atoms bond with each other because of these electrons, and there are two types of bonds: ionic and covalent.
Become a chemist; learn this essential chemistry terminology!
Now we’ve covered the basic chemistry terms, let’s take a look at some words that you’ll hear flying around your chemistry department.
Molecules make up substances, which can be found in three different states. These you will probably have heard already, but it is important to remember that a substance can change its state due to heat and pressure.
Substances can be pure elements, compounds, or mixtures. In chemistry, a mixture is defined as a substance made of two or more elements combined, but not chemically bonded like a compound.
There are different types of compounds, some of which most basic chemistry courses will require you to know:
Finally, in this section, we have acids and alkalis. These are opposites. Acids contain hydrogen, donate protons and make positive ions in water. Alkalis produce negative ions in water. You’ll see this again below, but if you want something a little more in depth, try out our piece on the central concepts in chemistry.
Salt is a chemical compound that you need to know!
For most GCSE chemistry courses, you will need to know some basic terms for chemical reactions – or you will never understand what happens in the laboratory or in an experiment!
Firstly, you need to know the three terms of a chemical reaction. These are…
All reactions are either endothermic or exothermic, meaning they either take in energy or give it out.
In this table, you can find some important words for the main types of reaction you will be dealing with:
|Oxidation||A reaction, usually involving oxygen, in which an electron is lost.|
|Reduction||When electrons are added to an atom (the opposite of the above!)|
|Distillation||When a mixture loses a liquid by evaporation and condensation.|
|Thermal Decomposition||Breaking a compound into two or more substances by heating.|
|Titration||If you know the concentration of a solution, you can use titration to determine the concentration of a different solution.|
Understanding the textbook terms used in your chemistry course is not only about knowing the atomic structures of states of matter. You also need to know the ways in which a chemist might make a calculation or measure a given substance. This indispensable terminology will help in any chemistry class.
You will also need to know another scale, the pH scale. This is used to describe how acidic or alkali a substance is. It ranges from 0 to 14, with the most acidic having the lowest number and the most alkali having the highest. Neutral substances are pH7.
Any introduction to chemistry vocabulary would be lacking without a mention of the most important equipment any scientist might use in their labs. Chemistry is not only theoretical and analytical, but empirical and therefore practical too!
Check out more in our article on the basic chemistry kit.
A Bunsen burner is a key term in your chemistry equipment glossary.
Remember that chemistry affects us every single day. Why not read up on some life-changing chemistry discoveries whilst you’re here?