Question

An oxide of nitrogen contains $36.8\%$by weight of nitrogen. The formula of the compound is :
A.${N_2}O$
B.${N_2}{O_3}$
C.$NO$
D.$N{O_2}$

Answer 1

Nitrogen oxides are a group of seven gases and compounds composed of nitrogen and oxygen and sometimes they are collectively known as $N{O_X}$ gases. The two most common and hazardous oxides of nitrogen are nitric oxide and nitrogen dioxide. Both are formed during high-temperature combustion in the atmosphere.
Formula used:
No of moles$= \dfrac{{given mass}}{{molar mass}}$

Complete step by step answer:
Now, for the given question, let’s assume that the weight of the compound is $100g$.
Now, weight of nitrogen is given i.e. $36.8gm$
Therefore, number of moles of nitrogen $= \dfrac{{36.8}}{{14}}$ (according to the given formula)
Therefore, weight of oxygen $= 100 - 36.8$
$= 63.2g$
So, number of moles of oxygen $= \dfrac{{63.2}}{{16}}$
Now, we will find out the ratio of number of moles of N and O:
So, N: O $= \dfrac{{36.8}}{{14}}:\dfrac{{63.2}}{{16}}$
$= 2.628:3.95$
$= 1:15$
$= 2:3$
So, the formula is ${N_2}{O_3}$

Hence, option B is correct.

Note:
Nitrogen oxides are produced in combustion processes. They are produced partly from nitrogen compounds in the fuel but mostly by direct combination of atmospheric oxygen and nitrogen. These are also produced by lightning and also by microbial processes in soils up to some extent. Nitrogen oxides are harmful to the respiratory tract, eyes and skin. When inhaled, they can cause asthma and coughing problems