Isotope: Definition, Types.

Definition:

• Atoms with same atomic number (number of proton), but different atomic weight (number of protons and neutrons).
• Atoms of same element with different atomic weight.

Types of isotope:

1. Stable isotope
• Stability of an isotope depends on the definite neutron to ration which is specific for a specific atom.
• In atoms of low atomic weight stability is usually achieved with neutron to proton ration around one.
• In atoms of high atomic stability is usually achieved with more neutron than proton
• Neutrally occurring isotopes of most of the predominant elements are stable isotopes.
2. Unstable isotope
• These are the isotopes having neutron to proton ration far away from its stability ratio.
• Neutrally occurring isotopes of heavy elements are usually unstable
• Rarely some naturally occurring isotopes of lighter elements can also be unstable
• Unstable isotopes tend to become stable by radio active decay