Question

How many grams are contained in 3.22 moles of dinitrogen tetroxide?

Answer 1

Hint: The chemical formula of dinitrogen tetroxide is ${{N}_{2}}{{O}_{4}}$. To answer this question we should know the formula to calculate the number of moles. This will give us a lead to solve the problem.

Complete step by step answer:
Mole is a Latin word which means heap or mass. The mole is defined as the amount of a substance containing as many atoms, molecules, ions, electrons or other elementary entities as there are carbon atoms in exactly 12g of C-12. The number of moles can be represented as 'n'.
Given:
n = 3.22
The formula to calculate number of moles is:
Number of moles = \[\dfrac{weight\text{ }in\text{ }g}{Molecular\text{ }weight\text{ }in\text{ }g}\]…….equation 1
Now, we should calculate the molecular weight of ${{N}_{2}}{{O}_{4}}$ in the first place.
Molecular weight = Atomic weight of nitrogen $\times $2 + Atomic number of oxygen $\times $ 4
Atomic number of nitrogen = 14 g
Atomic number of oxygen = 16 g
So, Molecular weight = 14 $\times $ 2 + 16 $\times $ 4
= 28 + 64
= 92 g
Now let's substitute the value of n and molecular weight in equation 1,
3.22 = $\dfrac{Weight\text{ in }g}{92}$
Weight of ${{N}_{2}}{{O}_{4}}$ in g = 3.22 $\times $ 92
 = 296.24 g
Thus, the weight of ${{N}_{2}}{{O}_{4}}$ is 296.24 g

Note: Moles can be represented or defined as follows:
-Number of moles of molecules = \[\dfrac{weight\text{ }in\text{ }g}{Molecular\text{ }weight\text{ }in\text{ }g}\]
- Number of moles of atoms = \[\dfrac{weight\text{ }in\text{ }g}{\text{Atomic }weight\text{ }in\text{ }g}\]
- Number of moles of gases = \[\dfrac{Volume\text{ }in\text{ }NTP}{Standard\text{ }molar\text{ }volume}\]
-Number of moles of atoms/molecules/ions/electrons =\[\dfrac{Number\text{ }of\text{ }atoms/molecules/ions/electrons}{Avogadro\text{ }constant}\]
-Number of moles of solute = Molarity $\times $ Volume of solution (in liters)
According to our need we can use the appropriate formula and answer this question within no time.