Question

Group of atoms is called as

Answer 1

Atoms is the smallest part of an element. I is the building block of matter.an atom is smallest constituent
unit of matter that has properties of a chemical element. Atoms join together to form molecules.molecule is the group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in Chemical reactions.

Answer 2

Group of atoms is called as molecule.

A molecule consists of two or more atoms which are held together by chemical bonds .A water molecule is made up of two atoms hydrogen (H) and one atom of Oxygen(o).

Thus the chemical formula of water is H2O.
Elements also frequently occur in molecular forms .For example two atoms of chlorine oxygen and nitrogen combine to from Cl2, O2,N2 respectively .There are complicated molecules as well as those of plastic.

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ATOM IS THE SMALLEST PARTICLE .IT CONSISTS OF POSITIVELY CHARGED PROTONS AND AND EQUAL NUMBER OF NEUTRONS.

ELEMENT IS PURE SUSBSTANCE CONSISTING OF ATOMS OF SAME KIND.

Hope this will help you...