posted by pranu on .
An allotrope is a variant of a substance consisting of only one type of atom. It is a new molecular configuration, with new physical properties. Substances that have allotropes include carbon, oxygen, sulfur, and phosphorous. Allotropes of a given substance will often have substantial differences between each other.
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Example;-Oxygen exists as two gaseous allotropes,'normal oxygen(O2)and (Ozone(O3),which differ in their molecular configurations.