Search results for “pH”

Markovnikov's Rule Organic Chemistry Dimensionless In the addition of a protic acid to an unsymmetrical alkene, the hydrogen attaches to the carbon already bearing more hydrogens.

Mole Fraction Solutions & Colligative Properties Dimensionless The ratio of the moles of one component to the total moles of all components in a mixture. x_A = n_A / n_total

Molecular Equation Stoichiometry & Chemical Reactions Dimensionless A chemical equation in which all reactants and products are written as complete, undissociated formulae. AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)

Monosaccharide Biochemistry & Polymer Chemistry Dimensionless The simplest carbohydrate, which cannot be hydrolysed into smaller sugar units. (CH₂O)ₙ

Nernst Equation Electrochemistry & Redox V The equation relating a cell's potential to the concentrations of the species involved. E = E° − (RT/nF) ln Q

Neutral Solution Acids, Bases & Salts mol/L A solution in which the concentrations of hydrogen and hydroxide ions are exactly equal. [H⁺] = [OH⁻] = √Kw

Node Atomic Structure & Periodicity Dimensionless A region within an orbital where the probability of finding an electron falls to zero. total nodes = n − 1

Nuclear Cross Section Nuclear & Radiochemistry barn A measure of the probability that a particular nuclear reaction will occur between a nucleus and an incident particle. σ, measured in barns

Nucleic Acid Biochemistry & Polymer Chemistry Dimensionless A biopolymer of nucleotides that stores and transmits genetic information.

Nuclide Nuclear & Radiochemistry Dimensionless A distinct species of atom characterised by a specific number of protons and neutrons in its nucleus. ᴬ_Z X

Optical Isomerism Organic Chemistry degrees Stereoisomerism in which molecules are non-superimposable mirror images and rotate plane-polarised light in opposite directions.

Packing Efficiency States of Matter & Gas Laws Dimensionless The percentage of the total volume of a unit cell that is actually occupied by the constituent particles. (volume of atoms / cell volume) × 100

Parts per Million Solutions & Colligative Properties ppm A concentration unit expressing one part of solute per million parts of solution by mass or volume. ppm = (m_solute / m_solution) × 10⁶

Penetrating Power Nuclear & Radiochemistry mm The depth to which a given type of radiation can travel into a material before being absorbed.

Percentage Purity Stoichiometry & Chemical Reactions Dimensionless The proportion of a sample that consists of the desired compound, expressed as a percentage of the total mass. % purity = (mass pure / mass sample) × 100

Percentage Yield Stoichiometry & Chemical Reactions Dimensionless The actual yield expressed as a percentage of the theoretical yield. % yield = (actual / theoretical) × 100

pKa Acids, Bases & Salts Dimensionless The negative logarithm of the acid dissociation constant, giving a convenient scale of acid strength. pKa = −log Ka

pOH Acids, Bases & Salts Dimensionless The negative logarithm of the hydroxide ion concentration. pOH = −log[OH⁻]; pH + pOH = 14

Positron Emission Nuclear & Radiochemistry MeV Radioactive decay in which a proton converts into a neutron, emitting a positron and a neutrino. p → n + e⁺ + ν

Pressure Equilibrium Constant Chemical Equilibrium Various The equilibrium constant for a gaseous reaction expressed in terms of partial pressures. Kp = p_C^c p_D^d / p_A^a p_B^b

Primary Structure Biochemistry & Polymer Chemistry Dimensionless The linear sequence of amino acids in a polypeptide chain.

Primary Valence Inorganic & Coordination Chemistry Dimensionless In Werner's theory, the ionisable valence of a metal, equal to its oxidation state and satisfied by negative ions.

Proton Affinity Acids, Bases & Salts kJ/mol The energy released when a gaseous species accepts a proton, measuring intrinsic basicity free of solvent effects. B(g) + H⁺(g) → BH⁺(g)

Purity Foundations of Chemistry Dimensionless The mass fraction of the desired substance in a sample, usually expressed as a percentage of the total mass. purity % = (mass of pure substance / total mass) × 100

Results for “pH”