Question

What is the particle that moves around the outside of the nucleus?
A) Neutrons
B) Protons
C) Electrons
D) All of the above

Answer 1

Hint: We need to know that the neutrons, protons and electrons are the units that are present in an atom. Protons and neutrons have approximately equal mass whereas the number of protons and electrons are equal in an atom.

Complete step by step answer:
Let’s study the structure of an atom, which makes it easier to answer this question.
An atom is the smallest unit of any matter. Matter can be solid, liquid or gases. The size of an atom is approximately \[100pm\]. Every atom contains a nucleus and nucleus further contains subatomic particles that are protons and neutrons.
Number of protons is equal to the atomic number of an atom or element.
An atom is surrounded by certain orbits at which electron revolves.
Number of electrons is equal to the atomic number of an atom or element.
An element is a species that contains the same atoms.
For Example:\[Cl\],\[Fe\].
We need to know that an atom has a given mass which is approximately equals to mass number which can also be defined as twelfth of the mass of free neutral atom of $C - 12$ i.e. approximately\[1.66 \times {10^{ - 27}}kg\].
Since protons and neutrons are heavy therefore they are present at the centre of an atom whereas electrons being lightweight moves at the orbits outside an atom.
Protons are positively charged particles; electrons are negatively charged particles whereas neutrons are uncharged species.
Option A) this option is incorrect as neutrons are the species that are present inside the nucleus.
Option B) This is an incorrect option as protons are the species that are present inside the nucleus.
Option C) this is a correct option as electrons are the one that moves around circular orbits outside the nucleus.
Option D) this option is incorrect as all of the above cannot be the answer.

Hence, the correct answer is, ‘Option C’.

Note: The protons and neutrons are present in the nucleus which is present at the centre of an atom and an electron revolves in a circular path around an atom which is called an orbit.