Lewis acid
A species capable of accepting an electron pair; e.g., BF 3.
Lewis base
A species capable of donating an electron pair; e.g., NH 3.
Lewis structure
A method of representing the shared and unshared electrons of an atom, molecule, or ion.
Limiting reagent
In a chemical reaction, the reactant present in such quantity as to limit the amount of product that
can be formed.
Liquid
The state of matter in which intermolecular attractions are intermediate between those in gases
and in solids, distinguished from the gas phase by having a definite volume and from the solid phase
in that the molecules may mix freely.
Litmus
An organic substance that is used as an acid-base indicator, most often in paper form. It turns red in
acidic solution and blue in basic solution.
London force
See Dispersion force.
Magnetic quantum number (ml)
The third quantum number, defining the particular orbital of a subshell in which an electron resides.
It conveys information about the orientation of the orbital in space (e.g., px versus py).