In
chemistry
Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules a ...
, the effective molarity (denoted ''EM'')
is defined as the ratio between the first-order rate constant of an
intramolecular reaction
In chemistry, intramolecular describes a Chemical process, process or characteristic limited within the Chemical structure, structure of a single molecule, a property or phenomenon limited to the extent of a single molecule.
Relative rates
In i ...
and the second-order rate constant of the corresponding intermolecular reaction (''kinetic effective molarity'')
or the ratio between the
equilibrium constant
The equilibrium constant of a chemical reaction is the value of its reaction quotient at chemical equilibrium, a state approached by a dynamic chemical system after sufficient time has elapsed at which its composition has no measurable tendency ...
of an
intramolecular reaction
In chemistry, intramolecular describes a Chemical process, process or characteristic limited within the Chemical structure, structure of a single molecule, a property or phenomenon limited to the extent of a single molecule.
Relative rates
In i ...
and the
equilibrium constant
The equilibrium constant of a chemical reaction is the value of its reaction quotient at chemical equilibrium, a state approached by a dynamic chemical system after sufficient time has elapsed at which its composition has no measurable tendency ...
of the corresponding intermolecular reaction (''thermodynamic effective molarity'').
:
:
EM has the dimension of concentration. High EM values always indicate greater ease of intramolecular processes over the corresponding intermolecular ones. Effective molarities can be used to get a deeper understanding of the effects of intramolecularity on reaction courses.
See also
*
Cyclic compound
A cyclic compound (or ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring. Rings may vary in size from three to many atoms, and include examples where ...
*
Intramolecular reaction
In chemistry, intramolecular describes a Chemical process, process or characteristic limited within the Chemical structure, structure of a single molecule, a property or phenomenon limited to the extent of a single molecule.
Relative rates
In i ...
*
Macrocycle
Macrocycles are often described as molecules and ions containing a ring of twelve or more atoms. Classical examples include the crown ethers, calixarenes, porphyrins, and cyclodextrins. Macrocycles describe a large, mature area of chemistry. ...
*
Polymerization
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many fo ...
References
{{Reflist
Physical organic chemistry