Question

Sir can molecule have only one atom... Trying to understand monoatomic molecule..

Answer 1

Yes and no.

The most basic definition of molecule is an electrically neutral group of two or more atoms held together by chemical bonds. In that sense, no, a molecule cannot be made of a single atom, by definition.

In problems involving gases, however, the word molecule is often applied to any freely-moving particle, regardless of how many atoms it has. So a helium atom would be thought of as a molecule for the purpose of applying gas laws.This is called a monoatomic molecule.

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