Chemical species

Chemical species 

 

Chemical species are atoms, molecules, molecular fragments, ions, 

 etc., being subjected to a chemical process or to a measurement. Generally, a chemical species can be defined as an ensemble of chemically identical molecular entities that can explore the same set of molecular energy levels on a defined time scale.

 

The  common chemical species are :

1.  Ions 
2. Molecular Ions
3. Free radical
4. Neutral molecules

Ions

      An atom or group of atom having positive or negative charge is called ion.

 

Positive Charge

                         When atoms lose one or more electron  positive ion are formed.

                                       

                                              A                                     A⁺   + Ie^-

                                              H                                     H⁺  +  Ie^-

^{Charge on cation depends upon the number of electrons lost.}

^{Negative charge} 

                          ^{When atom add one or more electrons , anion are formed.}

                                                  A   + Ie^-                       A^-

                                                  H  +  Ie^-                       H^-

 ^{Charge on cation depends upon the number of electrons added.}