Technical Terms
Below are a list of technical terms often used in the world of chemistry. Click on the images to get a better look!
C
Colloidal Suspension
A substance that has microscopic particles suspended throughout it. These suspensions are often liquid and although the microscopic particles are dispersed, not dissolved, colloidal suspensions are stable mixtures.
Combustion
A chemical reaction that releases heat often accompanied with a flame. Combustion requires fuel, oxygen and heat. Complete combustion occurs when the only products are water and carbon dioxide. Incomplete combustion occurs when the products consist of molecules other than water and carbon dioxide like carbon monoxide or metal containing compounds.
Covalent Bond
A type of chemical bond that is formed when two elements share valence electrons. Elements can share two electrons, four electrons or even six electrons which form single bonds, double bonds, and triple bonds respectively. Covalent bonds are often found between two nonmetallic metals such as oxygen.
E
Endothermic and Exothermic Reactions
An endothermic reaction is a chemical reaction where energy is consumed. Energy can be inputted into a reaction through forms such as heat or kinetic energy (i.e. stirring). An exothermic reaction is a chemical reaction where energy is released. Energy can be released in different forms such as light or heat.
F
Functional Group
A functional group is a fancy way to describe areas of reactivity on a molecule. Functional groups will influence a molecule’s physical and chemical properties, meaning that when a chemical reaction occurs it almost always involves functional groups. Examples of functional groups include hydroxyls (O-H), thiols (S-H), and alkenes (C=H).
I
Ionic Bond
A type of chemical bond that is formed when two elements exchange valence electrons. A cation donates its electrons to an anion. This gives cations a positive charge and anions a negative charge. The two ions form an electrostatic bond since their opposite charges attract one another. Ionic bonds are often found between metallic elements and nonmetallic elements.
M
Miscible
The ability for two chemicals to be mixed together and fully dissolve into one another; the result is a homogenous solution. A great example of this is the age-old “like dissolves like” chemistry rule. A polar molecule, like water, will be miscible with another polar molecule, like ethanol, to form a solution. Oil and water are examples of two immiscible molecules since the former is polar and the latter is non polar.
O
Organic
When chemists refer to organic substances, they don’t mean grown without pesticides/herbicides like you would see in the grocery store. Organic molecules are a class of molecules that consist of elements like Hydrogen, Carbon, Nitrogen and Oxygen. Organic molecules do not contain any metallic elements (i.e. Alkali Earth Metals, Transition Metals, etc.). Click on the photo for some examples of organic molecules.
P
Photon
A photon is part of Isaac Newton’s wave-particle duality theory. This theory states that light has properties of both particles and waves. In this theory. photons act as the tiny particles of light! Photons move at the speed of light and have discrete amount of energies.
Polymer
A chemical composed of many smaller, repeating chemical units. These materials can occur naturally (i.e. rubber and wood) or can be manufactured such as many plastics. The smaller, repeating units of a polymer are called monomers. Monomers will bond together during a reaction called polymerization. This reaction can be easily controlled allowing chemists to dictate the size of the polymer and the physical characteristics (i.e. rigidness or stretchiness).
S
Semiconductor
A material’s ability to conduct is based on its ability to facilitate the flow of electrons (or think of the flow of electricity). A semiconductor is a poor conductor and a poor insulator. Semiconductors have two discrete energy bands: a conduction band and a valence band. The energy difference between the two bands is called a band gap. Once a semiconductor receives enough energy to overcome the band gap, electrons are promoted from the valence band to the conduction band and the semiconductor begins to conduct.
Solvent
A substance that dissolves or disperses another substance. The substance that is dissolved in a solvent is called a solute. Together, a solvent and a solute form a solution - a homogenous mixture or two or more substances. For example take ocean water(solution): it has salt (solute) and water (solvent)!
Synthesize
When a chemist refers to “synthesizing” something, they essentially mean making something. Synthesis is the production of compounds and molecules by reacting two or more other chemicals/molecules. The reactants are on the left side of a chemical equation and the products are on the right.
V
Valence Electron
Elements are composed of many electrons. Electrons exist at discrete energy levels within an element depending on their average distance from the nucleus. The greater the distance the lower the energy. Valence electrons exist at the most outer energy level (furthest from the nucleus). These electrons can be lost or gained during a chemical reaction to form bonds.