Ionization involves gaining or losing electrons to acquire a positive or negative charge, requiring energy from within the atom. Dissociation is the separation of ionic compounds into ions or radicals by an external force, with dissociation energy measuring the enthalpy change of bond cleavage. Key differences are that ionization is a physical process while dissociation occurs through an external reaction force and involves splitting ionic compounds rather than single atoms or molecules.

1. Dissimilarity b/w
Ionization & Dissociation
Hassan Raza Aslam
261-FBAS/BSBT/F-12
Pharmaceutical Chemistry

2. Ionization:
• Is the process by which an atom or
a molecule acquires a negative or positive
charge by gaining or losing electrons.
• In this reaction force comes from with in the
atom
• Ionization Energy; minimum amount of energy
needed to remove an electron.
• In Periodic Table ionization energy decreases
down the Group & increases along the Periods.

3. Ionization:
• Ionization is the physical process.
• General equation:
•
X + energy → X+ + e• E-g
HNO3 → H⁺ + NO3ˉ

4. Dissociation:
• Process in which ionic compounds separate or
split into smaller
particles, ions, or radicals, usually in a
reversible manner.
• In this reaction force comes from outside of
the atom.
• Dissociation Energy; the standard enthalpy
change when a bond is cleaved by homolysis.
• General Equation:
•
AB ====ˋ A + B

5. Conti…
• Dissociation Constant: is the ratio of
dissociated to undissociated compound.
• brackets denote the equilibrium
concentrations.