Question

For the reaction ${N_{2(g)}} + 3{H_{2(g)}} \to 2N{H_{3(g)}}$ . How many moles of ${N_2}$ will be needed to react with $1$ mole of ${H_2}$ ?

Answer 1

Firstly, we need to know what we mean by a mole. A mole can be defined as the amount of substance. 1 mole of a substance contains $6.022 \times {10^{23}}$ particles which can be either atoms, molecules or ions. Usually the concentration of a solution is commonly expressed by its molarity, which is defined as the amount of dissolved substance in mole per unit volume of the solution, denoted as M.

Complete answer:
In the equation that is given: ${N_{2(g)}} + 3{H_{2(g)}} \to 2N{H_{3(g)}}$
From the equation we know that $1$ mole of nitrogen reacts with $3$ moles of hydrogen to produce $2$ moles of ammonia.
These moles are obtained from the coefficients of the substances in the balanced chemical equation.Hence, the number of moles required to react with $1$ mole of hydrogen is calculated by using the following concept,
$1$ mole nitrogen $= 3$ moles hydrogen
x mole nitrogen $= 1$ mole hydrogen
x mole nitrogen $= \dfrac{{1 \times 1}}{3}$ moles
$x = 0.33$ moles nitrogen
Therefore, we can say that $0.33$ moles of nitrogen is required to $1$ mole of hydrogen.

Note: The mole is basically a count of particles. Usually these particles which are counted are chemically identical entities, or individually distinct. A solution may contain a certain number of dissolved molecules that are more or less independent of each other. Thus the solid is composed of a certain number of moles of particles. In compounds like diamond, where the entire crystal is a single molecule, and the mole is still used to express the number of atoms which are bound together, rather than a count of multiple molecules. The mass of 1 mole of a substance is equal to its relative atomic or molecular mass in grams.