Question

How many atoms of nitrogen are in $10g$ of $N{H_4}N{O_3}$ ?

Answer 1

Hint: In chemistry, various atoms and molecules react in various ways to form compounds with various properties and structures. The compounds that exist in nature can be similar in many ways based on the properties, method of formation or the structure or orientation. This similarity in property can be used to categorise various compounds and infer various properties of the group as a whole.

Complete step by step answer:
There are various compounds that exist in nature so there needs to be some grouping that needs to be defined for the categorisation of the compounds so that it is easier for the study of these elements and compounds as they can be tested as a bulk batch.
There are various properties that can be used for drawing a similarity study, one of the properties that can be used for this purpose is the molecular formula.
The molecular formula of the compound is the representation of the atoms and molecules that bond together to form the compound. It contains the number and kind of atoms that react to form the compound.
Moles is the SI unit for the number of particles and it is the amount that contains exactly $6.022 \times {10^{23}}$ particles
The moles of the compound can be calculated from the equation given as
$Moles = \dfrac{{mass}}{{molar\; mass}}$
So the moles of the compound in the question will be
$moles = \dfrac{{10}}{{80}} = 0.125$ as the information of the mass is given in the question.
So since $1mol$ of the substance contain $6.022 \times {10^{23}}$ particles
So $0.125$ moles must contain $0.125 \times 6.022 \times {10^{23}}$ particles

Thus, the number of atoms of nitrogen are $7.52 \times {10^{22}}$ particles.

Note: While molality is represented by $m$ another representation, Molarity is represented by $M$.
Molarity of the solution can be represented in terms of the volume of the solution rather than the mass of the solvent as in case of molality.
For the quantitative representation of the concentration of the solution there are several ways that can be used, molality is one of those criteria.
Molality is represented by $m$ and can be calculated by the following formula
$Molality(m) = \dfrac{{{\text{Moles of solute}}}}{{{\text{Mass of solvent in kg}}}}$