Below is a list of chemistry terms with a brief definition.
acid – a chemical species that accepts electrons or donate protons or hydrogen ions.
acid-base indicator – a weak acid or weak base that changes color when the concentration of hydrogen or hydroxide ions changes in an aqueous solution.
air – the mixture of gases that make up the Earth’s atmosphere, consisting mainly of nitrogen, with oxygen, water vapor, argon, and carbon dioxide.
alkaline – an aqueous solution with a pH greater than 7.
alkene – a hydrocarbon containing a double carbon-carbon bond.
aqueous solution – a solution in which water is the solvent.
atomic number – the number of protons in the nucleus of an atom of an element.
Avogadro’s Law – relation that states equal volumes of all gases contain the same number of molecules at the same pressure and temperature.
Avogadro’s number – the number of particles in one mole of a substance; 6.0221 x 1023
balanced equation – chemical equation in which the number and type of atoms and the electric charge is the same on both the reactant and product sides of the equation.
barium – alkaline earth metal with element symbol Ba and atomic number 56.
beryllium – alkaline earth metal with element symbol Be and atomic number 4.
beta decay – type of radioactive decay that results in spontaneous emission of a beta particle.
beta particle – an electron or positron emitted during beta decay.
beta radiation – ionizing radiation from beta decay in the form of an energetic electron or positron.
binary acid – an acidic binary compound in which one element is hydrogen and the other element is another nonmetal.
binary compound – a compound made up of two elements (e.g., HF).
binding energy – energy needed to remove an electron from an atom or to separate a proton or neutron from the atomic nucleus.
biochemistry – Biochemistry is the chemistry of living things.
bismuth – Bismuth is the name for the element with atomic number 83 and is represented by the symbol Bi. It is a member of the metal group.
bitumen – natural mixture of polycyclic aromatic hydrocarbons (PAHs).
black light – a lamp that emits ultraviolet radiation or the invisible radiation emitted by it.
block copolymer – copolymer formed by repeating monomer subunits.
boiling – phase transition from the liquid to gas state.
boiling point – temperature at which a liquid’s vapor pressure is equal to the external gas pressure.
boiling point elevation – the increase in a liquid boiling point caused by adding another compound to it.
bond – a chemical link formed between atoms in molecules and molecules and ions in crystals.
bond order – a measure of the number of electrons involved in chemical bonds between two atoms in a molecule; usually equal to the number of bonds between the atoms.
boron – Boron is the name for the element with atomic number 5 and is represented by the symbol B. It is a member of the semimetal group.
branched chain alkane – an alkane with alkyl groups bonded to the central carbon chain. The molecules are branched, but all C-C bonds are single bonds.
brass – Brass is defined as an alloy of copper and zinc.
bromine – Bromine is the name for the element with atomic number 35 and is represented by the symbol Br. It is a member of the halogen group.
bronze – Bronze is an alloy of copper, usually containing tin as its main addition.
conservation of energy – law which states energy can change forms but may not be created or destroyed.
conservation of mass – law that states, in a closed system, matter can change forms but not be created or destroyed.
copper – Copper is the name for the element with atomic number 29 and is represented by the symbol Cu. It is a member of the transition metals group.
covalent bond – chemical link between atoms or ions in which the electron pairs are more or less evenly shared between them.
covalent compound – molecule that contains covalent chemical bonds.
electron – stable negatively charged subatomic particle.
energy – the ability to do work (e.g., kinetic energy, light).
emulsifier – stabilizing agent that prevents immiscible liquids from separating.
exothermic reaction – a chemical reaction that releases heat.
