Questions & Answers

The size of atom is of the order of:
A. ${10^{ - 14}}m$
B. ${10^{ - 12}}m$
C. ${10^{ - 10}}m$
D. ${10^{10}}m$

Answer Verified Verified
Hint: We studied atoms in modern physics. The matter is made up of so many small atoms, atoms are the smallest constituent unit of matter that possesses all the properties of the chemical element. Dolton was the first scientist who gave theory about atoms and molecules of matter. His theory is known as Dalton’s atomic theory which states that all matter is made up of atoms that are indivisible. Molecules are made up of one or more atoms bound together by covalent bonds.

Complete step-by-step solution:
Basically every atom is a chemical element such as \[H, Fe, Na\], etc. Every atom is made up of very small particles known as electrons, protons, and neutrons. Atoms have a spherical shape which has a nucleus at its center
Electrons have a negligible mass in comparison to neutrons and protons. Protons and neutrons have nearly the same mass. It is very hard to measure the size of atoms because the electrons do not have a definite location surrounding the nucleus. However, we can find the atomic radius by calculating the distance from the center of the nucleus to the limits of the surrounding shells of electrons. There are three definitions that are widely used in defining the atomic radius: ionic radius, covalent radius, and Van Der Waals radius.
Atomic radius is approximately $r \approx {10^{ - 10}}m$. The Radius of the nucleus is $r' \approx {10^{ - 15}}m$. So,
$\dfrac{{{V_{atomic}}}}{{{V_{nucleus}}}} = {\left( {\dfrac{{{r_{atom}}}}{{{r_{nucleus}}}}} \right)^3} = {10^{15}}$, volume of atom is ${10^{15}}$ times greater than the volume of nucleus.
In the given question option C is correct.

Note: We know that nuclei of an atom consist of protons and neutrons hence it is positively charged. While the electrons occupy the area around the nucleus and it is negatively charged particles. Protons carry the positive charge and a neutron has no charge.