Question

What is meant by mole?

Answer 1

The mole term is a convenient way of expressing a substance's quantity. Any calculation has two parts: the numerical magnitude and the units in which the numerical magnitude is expressed. The magnitude is ‘$2$' and the unit is ‘kilogramme' when the mass of a ball is determined to be $\;2$kilogrammes.

Complete answer:
Even one gram of a pure element is considered to contain a large number of atoms when interacting with particles at the atomic (or molecular) level. The mole term is commonly used in this context. It is mainly concerned with the 'mole,' which is a count of a large number of particles.
A mole is known in chemistry as the sum of a substance that contains exactly $6.02214076{\text{ }} \times {10^{23}}$ of the substance's "elementary entities."
The Avogadro constant is the number $6.02214076 \times {10^{23}}$ that is often denoted by the symbol ${N_A}$. Atoms, molecules, monatomic/polyatomic ions, and other particles are examples of elementary entities that can be expressed in moles (such as electrons).
One mole of pure carbon-$12$ ($^{12}C$) has a mass of exactly $\;12$ grams and contains $6.02214076 \times {10^{23}}$(${N_A}$) number of $^{12}C$ atoms, for example. The following formula can be used to calculate the number of moles of a substance in a pure sample:
$n = \dfrac{N}{{{N_A}}}$
Where n is the number of moles of the substance (or elementary entity), N is the total number of elementary entities in the sample, and ${N_A}$ is the Avogadro constant.

Note:
The term "mole" was coined in 1896 by German chemist Wilhelm Ostwald, who derived it from the Latin word moles, which means "heap" or "pile."