Chemistry terms starting with M

Magic Numbers Nuclear & Radiochemistry Dimensionless Particular numbers of protons or neutrons that give a nucleus exceptional stability. 2, 8, 20, 28, 50, 82, 126

Magnetic Moment of Complexes Inorganic & Coordination Chemistry BM The magnetic behaviour of a complex, determined by the number of unpaired electrons it contains. μ = √(n(n+2)) BM

Magnetic Quantum Number Atomic Structure & Periodicity Dimensionless The quantum number mₗ that specifies the spatial orientation of an orbital relative to an applied magnetic field. mₗ = −l … 0 … +l

Magnitude of K and Extent of Reaction Chemical Equilibrium Dimensionless The use of the size of the equilibrium constant to judge how far a reaction proceeds before equilibrium is reached. K ≫ 1: products favoured

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.

Mass Defect Nuclear & Radiochemistry u The difference between the mass of a nucleus and the sum of the masses of its constituent nucleons. Δm = Zm_p + Nm_n − m_nucleus

Mass Number Atomic Structure & Periodicity Dimensionless The total number of protons and neutrons in an atomic nucleus. A = Z + N

Mass Percentage Solutions & Colligative Properties Dimensionless The mass of solute expressed as a percentage of the total mass of the solution. % w/w = (m_solute / m_solution) × 100

Mass Spectrometry Analytical Chemistry & Spectroscopy Da A technique that separates ionised molecules and fragments according to their mass-to-charge ratio. m/z

Matrix Analytical Chemistry & Spectroscopy Dimensionless Everything in a sample other than the analyte itself.

Matter Foundations of Chemistry kg Anything that occupies space and possesses rest mass, existing in the solid, liquid, gas or plasma state.

Maximum Work Thermochemistry & Thermodynamics J The greatest amount of work obtainable from a change of state, achieved only along a reversible path. w_max = ΔA; w_max(non-pV) = ΔG

Maxwell–Boltzmann Distribution States of Matter & Gas Laws Dimensionless The statistical distribution describing how molecular speeds are spread within a gas at a given temperature. f(v) ∝ v² e^(−mv² / 2kT)

Melting Point States of Matter & Gas Laws °C The temperature at which the solid and liquid phases of a substance coexist in equilibrium at a given pressure. ΔG = 0 at T_m

Metabolism Biochemistry & Polymer Chemistry kJ/day The complete set of chemical reactions occurring within a living organism.

Metal Carbonyl Inorganic & Coordination Chemistry Dimensionless A coordination compound in which carbon monoxide molecules are bonded to a metal centre. M(CO)ₙ

Metallic Bond Chemical Bonding & Molecular Structure kJ/mol The attraction between a lattice of metal cations and the delocalised electrons that move freely throughout the structure.

Metallic Character Atomic Structure & Periodicity Dimensionless The tendency of an element to lose electrons and display typical metallic properties such as lustre, malleability and conductivity.

Metalloid Atomic Structure & Periodicity Dimensionless An element with properties intermediate between those of metals and non-metals, lying along the periodic table's staircase.

Metallurgy Inorganic & Coordination Chemistry Dimensionless The science and technology of extracting metals from their ores and preparing them for use.

Methyl Orange Acids, Bases & Salts Dimensionless An acid–base indicator that is red in acid and yellow in alkali, changing between pH 3.1 and 4.4. C₁₄H₁₄N₃NaO₃S

Micelle Solutions & Colligative Properties mol/L A spherical aggregate of surfactant molecules that forms in solution above a characteristic concentration.

Michaelis–Menten Kinetics Chemical Kinetics & Catalysis mol/(L·s) The standard model of enzyme kinetics, in which rate rises with substrate concentration until the enzyme becomes saturated. v = V_max[S] / (K_m + [S])

Mineral Inorganic & Coordination Chemistry Dimensionless A naturally occurring inorganic solid with a definite chemical composition and an ordered crystal structure.

Terms starting with M