Chemistry terms starting with B

Back Bonding Chemical Bonding & Molecular Structure kJ/mol The donation of electron density from a filled orbital on one atom into an empty orbital on its bonded partner, in the direction opposite to the sigma bond. M(dπ) → L(π*)

Back Titration Analytical Chemistry & Spectroscopy mol A technique in which excess reagent is added and the unreacted portion titrated to find how much reacted with the analyte. n_reacted = n_added − n_remaining

Background Radiation Nuclear & Radiochemistry mSv/year The ionising radiation always present in the environment from natural and artificial sources.

Balanced Chemical Equation Stoichiometry & Chemical Reactions Dimensionless An equation in which the number of atoms of each element and the total charge are identical on both sides. Σ atoms(left) = Σ atoms(right)

Band of Stability Nuclear & Radiochemistry Dimensionless The region on a plot of neutron number against proton number within which stable nuclides are found.

Base Acids, Bases & Salts Dimensionless A substance that accepts protons, produces hydroxide ions in water, or donates a pair of electrons. B + H⁺ → BH⁺

Base Dissociation Constant Acids, Bases & Salts mol/L The equilibrium constant for the reaction of a base with water to produce hydroxide ions. Kb = [BH⁺][OH⁻] / [B]

Base Pairing Biochemistry & Polymer Chemistry Dimensionless The specific hydrogen bonding between complementary nitrogenous bases in nucleic acids. A–T (2 H-bonds), G–C (3 H-bonds)

Base Peak Analytical Chemistry & Spectroscopy Dimensionless The most intense peak in a mass spectrum, assigned an arbitrary relative abundance of 100%.

Basic Buffer Acids, Bases & Salts Dimensionless A buffer made from a weak base and one of its salts, giving a pH above 7. pOH = pKb + log([salt]/[base])

Basic Salt Acids, Bases & Salts Dimensionless A salt whose aqueous solution has a pH above 7, or one that retains a hydroxide group.

Basic Solution Acids, Bases & Salts mol/L A solution in which the hydroxide ion concentration exceeds the hydrogen ion concentration. [OH⁻] > [H⁺]

Becquerel Nuclear & Radiochemistry Bq The SI unit of radioactivity, equal to one nuclear disintegration per second. 1 Bq = 1 s⁻¹

Beer–Lambert Law Analytical Chemistry & Spectroscopy Dimensionless The relation stating that absorbance is proportional to concentration and to the path length of the sample. A = ε c l

Bent Geometry Chemical Bonding & Molecular Structure degrees A molecular shape in which two bonded atoms form an angle at a central atom that also carries one or more lone pairs. AX₂E or AX₂E₂

Benzene Organic Chemistry Dimensionless The simplest aromatic hydrocarbon, a planar regular hexagon of six sp² carbons with a delocalised pi cloud. C₆H₆

Beta-Minus Decay Nuclear & Radiochemistry MeV Radioactive decay in which a neutron converts into a proton, emitting an electron and an antineutrino. n → p + e⁻ + ν̄

Bidentate Ligand Inorganic & Coordination Chemistry Dimensionless A ligand that binds to the same metal centre through two donor atoms, forming a ring.

Bimolecular Reaction Chemical Kinetics & Catalysis L/(mol·s) An elementary step in which two species collide and react. A + B → products, rate = k[A][B]

Binding Energy per Nucleon Nuclear & Radiochemistry MeV/nucleon The nuclear binding energy divided by the number of nucleons, measuring the stability of a nucleus. BE/A

Biochemistry Biochemistry & Polymer Chemistry Dimensionless The study of the chemical substances and processes that occur within living organisms.

Biodegradable Polymer Biochemistry & Polymer Chemistry Dimensionless A polymer that can be broken down into simple substances by the action of microorganisms.

Biomolecule Biochemistry & Polymer Chemistry Dimensionless An organic molecule produced by and essential to a living organism.

Blank Analytical Chemistry & Spectroscopy Various A sample containing everything except the analyte, measured to correct for background signal.

Terms starting with B