Question

The number of neutrons in one mole of hydrogen is-
A. ${N_A}$
B. $0.5{N_A}$
C. 0
D. $2{N_A}$

Answer 1

Hint: An atom is made up of three fundamental particles like electron, proton and neutron. Among these three, proton is positively charged and resides inside the nucleus, electron is negatively charged and revolves around the nucleus whereas neutron is neutral, i.e., having no charge. It also resides inside the nucleus along with protons.

Complete step by step answer:
Atomic number of an element is equal to the number of protons present in the nucleus of an atom, constituting that element.
Neutrons play a very vital role in providing stability to the atom. There are some atoms which lack neutrons. For e.g. Hydrogen atom $H$. It is having an atomic number equal to 1. This means the nucleus only contains one proton in this case and no neutron.
One mole of a substance can be defined as the amount of a chemical substance that contains as many elementary entities (atoms, molecules, ions, electrons, or photons), as there are atoms present in 12 grams of carbon-12 ($12C$ ), which is an isotope of carbon with relative atomic mass of 12 by definition. This number is known as Avogadro constant, ${N_A}$ . It has a value of $6.022 \times {10^{23}}mo{l^{ - 1}}$
Since an atom of hydrogen has no neutron, no matter how many moles of it we are considering. Therefore, there will be zero number of neutrons in 1 mole of hydrogen.

So, the correct option is C.

Note:
Hydrogen, having atomic number 1 is an odorless, tasteless and colorless gas. It is an abundant element and has a wide variety of uses in chemical industries.