A cathode is a type of electrode in which electrical current exits the polarized electrical circuit. Positively charges cations always move toward the cathode, and the opposite applies for the anode.

Lanthanides are a grouping of metallic elements which range from 57 to 71, from the elements lanthanum to lutetium. They can also be called lanthanoids.

The word alkali is usually seen before the word metal, and they are defined as any metallic element which belongs to Group 1 of the periodic table. Some examples include sodium, potassium and lithium.

Valency is defined as the combining capacity of an element or the measure of its combining powers when it forms a chemical compound or molecule.

Stoichiometry is the precise calculation of the reactants and the products in chemical reactions. It is founded on the law of conservation of mass, which states that the total mass of reactants equals the total mass of the initial products.

Electrolysis is a technique which used electrical current to drive a non-spontaneous chemical reaction, thereby producing changes in the substance.

A polymer is a large molecule which is made up of repeating subunits called monomers. They usually have high boiling and melting points and sometimes a high molecular mass.

A nucleophile is a chemical compound or species which donates an electron pair to an electrophile in order to form a chemical bond in a reaction. Molecules which have at least one pair of free electrons can act as nucleophiles.

A zwitterion is a chemical compound which has a net charge of zero, which makes it electrically neutral. It does, however, have both positive and negative charges in it.

An unsaturated compound is one which has a carbon to carbon double and/or triple bonds. Because of this bonding, it does not contain the highest amount of hydrogen atoms like the saturated compounds.

Beryllium is a chemical element which is represented by the symbol Be and the atomic number 4. The alkaline earth metal is relatively rare and can be found as a product of large atomic nuclei colliding with cosmic rays.

Effervescence is the escape of gases from an aqueous solution causing it to foam or fizz upon its release. An example of this is opening a carbonated beverage such as champagne.

Halogens are a group of non-metallic elements found in Group 17 of the periodic table. There are five of them (fluorine, chlorine, bromine, iodine, and astatine). They are known to form strong acidic compounds with hydrogen.

Deliquescence is the process by which a substance absorbs moisture from the atmosphere until it completely dissolves in the water, thereby forming a solution.

Malleability, also called ductility, is the measure of a material’s ability to undergo deformation before it breaks or ruptures. It is typically expressed as percent elongation.

An allotrope is an element which can exist in two or more forms. The differentiation can be in the way that they are bonded or the way that they are arranged.

Xenon is a chemical element which is represented by the symbol Xe and the atomic number 54. It is a colorless and odorless noble gas, and it can be found in products like flash lamps and general anesthesia.

A pipette is a laboratory tool which is used to transport, or store measured volumes of liquid. They come in several sizes and designs made from different materials including glass.

Palladium is a chemical element which is represented by the symbol Pd and the atomic number 46. The silvery white metal was discovered by William Hyde Wollaston and is used in dentistry, hydrogen purification and jewelry.

Tetrahedral is a word which describes the shape of a molecule that has one atom in the center and is bound to four atoms by chemical bonds at the corners. It is then known as a tetrahedron.

In chemistry, a carbonyl group is a functional group (substituents within molecules) which is composed of a carbon atom which is double bonded to an oxygen atom (C=O). Compounds containing this group are called carbonyl compounds.

A reagent is a substance which is added to a system to cause a chemical reaction, or to test whether a reaction did or can occur. The word is often interchanged with reactant but is a separate entity.

A catalyst is a substance which speeds up the rate of a chemical reaction but is not used up in the reaction; which means that it can be recovered after the reaction has occurred. Enzymes are examples of protein catalysts.

Saponification is the process by which fat or oil is converted into soap and alcohol by using heat in the presence of aqueous alkali. The fats used are animal fats or vegetable oil. In instances where they use sodium hydroxide, hard soap is produced.

An amphoteric compound is one that is able to react both as an acid and a base, depending on the medium, according to the Bronsted-Lowry theory. It comes from the Greek word “amphoteros,” which means “each or both of two.”

Ketones, also known as alkenone, is an organic compound which has the base structure RC(=O)R’. R and R’ being varieties of carbon-containing compounds.

Chelation is a type of bonding in which ions and molecules bind with metal ions. It involves the formation of two or more separate coordinate bonds between ligands and single central atoms.

Yttrium is a chemical element which is represented by the symbol Y and the atomic number 39. It is a silvery-metallic transitional metal which is found in LEDs, lasers, phosphors and electrodes.

Electromagnetism is the study of electromagnetic forces, which is the physical interaction that occurs between particles which are electrically charged. They typically exhibit electromagnetic fields and are one of the fundamental interactions in nature.

Heterogenous is used to describe a type of mixture which is a combination of two or more pure and dissimilar substances. In other words, the mixture has a non-uniform composition.

Ionization, sometimes spelled ionization, is the process by which a molecule or atom acquires a positive or negative charge by either gaining or losing electrons in order to form ions. One example, gas ionization, occurs within fluorescent lamps.

Resonance, also known as mesomerism, describes the delocalization of electrons within certain molecules or polyatomic ions where bonding cannot be expressed by a single Lewis structure.

Spectroscopy is the study of the interaction between electromagnetic radiation and matter. It splits the light into constituent wavelengths in a similar fashion to that of a prism with the different energy levels being quantified.

The viscosity of a fluid is the measure of its resistance to flow. Some people use thickness as a synonym to viscose, and one example includes honey or blood and water. The first two options are more viscose or thicker than water.

Centrifugation is a laboratory technique which involves using a centrifugal force to separate particles in solution according to its shape, size, viscosity and density. It is mostly used to separate two miscible substances.