Question

what is atom, molecules, atomic mass ​

Answer 1

Explanation:

Atom is simplest structure of any element.

Molecule is formed by two or more atoms.

e.g.H2,O2,N3

Atomic mass is the sum of number of protons and neutrons in the atom of an element.

The atomic mass increase with increase of atomic number.

Atomic number of an element and number of protons present is an atom is same.

Answer 2

$\huge\mathbb\orange{Heya\:Mate..!}$

${\huge{\red{\underline{\underline{\mathcal Atom }}}}}$

An atom a fundamental piece of matter. ... An atom itself is made up of three tiny kinds of particles called subatomic particles: protons, neutrons, and electrons. The protons and the neutrons make up the center of the atom called the nucleus and the electrons fly around above the nucleus in a small cloud.

${\huge{\red{\underline{\underline{\mathcal Molecule }}}}}$

A molecule is the smallest particle in a chemical element or compound that has the chemical properties of that element or compound. Molecules are made up of atoms that are held together by chemical bonds. These bonds form as a result of the sharing or exchange of electrons among atoms.

${\huge{\red{\underline{\underline{\mathcal Atomic Masses }}}}}$

The atomic mass is a weighted average of all of the isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope. (Atomic mass is also referred to as atomic weight, but the term "mass" is more accurate.)