- Elements 58 to 71 (after lanthanum)
- Lanthanide Contraction
- A decrease in the radii of the elements following the lanthanides compared
to what would be expected if there were no f-transition metals.
- Law of Combining Volumes (Gay-Lussac's Law)
- At constant temperature and pressure, the volumes of reacting gases ( and
any gaseous products) can be expressed as ratios of small whole numbers;
- Law of Conservation of Energy
- Energy cannot be created or destroyed; it may be changed from one form to
- Law of Conservation of Matter
- There is no detectable change in the quantity of matter during an
ordinary chemical reaction.
- Law of Conservation of Matter and Energy
- The total amount of matter and energy available in the universe is fixed.
- Law of Definite Proportions (Law of Constant Composition)
- Different samples of a pure compound always contain the same elements in
the same proportions by mass.
- Law of Partial Pressures (Dalton's Law)
- The total pressure exerted by a mixature of gases is the sum of the
partial pressures of the individual gases.
- Lead Storage Battery
- Secondary voltaic cell used in most automobiles.
- Leclanche Cell
- A common type of dry cell.
- Le Chatelier's Principle
- States that a system at equilibrium, or striving to attain equilibrium,
responds in such a way as to counteract any stress placed upon it.
- If a stress (change of conditions) is applied to a system at equilibrium,
the system shifts in the direction that reduces stress.
- Leveling Effect
- Effect by which all acids stronger than the acid that is characteristic of
the solvent react with solvent to produce that acid; similar statement applies
to bases. The strongest acid (base) that can exist in a given solvent is the
acid (base) characteristic of the solvent.
- Refers to an optically active substance that rotates the plane of plane
polarized light counterclockwise; also called levo.
- Lewis Acid
- Any species that can accept a share in an electron pair.
- Lewis Base
- Any species that can make available a share in an electron pair.
- Lewis Dot Formula (Electron Dot Formula)
- Representation of a molecule, ion or formula unit by showing atomic symbols
and only outer shell electrons
- A Lewis base in a coordination compound.
- Limiting Reactant
- Substance that stoichiometrically limits the amount of product(s) that can
- Linear Accelerator
- A device used for accelerating charged particles along a straight line
- Line Spectrum
- An atomic emission or absorption spectrum.
- Linkage Isomers
- Isomers in which a particular ligand bonds to a metal ion through different
- Liquid Aerosol
- Colloidal suspension of liquid in gas.
- London Forces
- Very weak and very short-range attractive forces between short-lived
temporary (induced) dipoles; also called dispersion Forces.
- Lone Pair
- Pair of electrons residing on one atom and not shared by other atoms;
- Low Spin Complex
- Crystal field designation for an inner orbital complex; contains electrons
paired t2g orbitals before eg orbitals are occupied in octahedral complexes.