Question

what is an atom and nucelus

Answer 1

atom  is the smallest particle of any substance which can divided into three parts ,which is divisible according to modern theory,it is the smallest particle which is nuetral,,,,nuceus is the place whole mass is focused ,,by the rutherford experiement he conclusion that when alpha particles passes through atom some of particles bounce back due to mass of the atom ,,this proves the discovery of nucleus

Answer 2

Heya friend
Here is the answer

Atom :
A unit of matter; the smallest unit of a chemical element. Each atom consists of a nucleus, which has a positive charge, and a set of electrons that move around the nucleus.

Nucleus :
The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom,

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