Question

A balanced reaction of conversion of ammonia to nitric oxide by catalytic oxidation of ammonia is:
A. \[4{\text{N}}{{\text{H}}_3} + 5{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}4{\text{NO}} + 6{{\text{H}}_2}{\text{O}} + \Delta \]
B. \[4{\text{N}}{{\text{H}}_3} + 3{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}4{\text{NO}} + 2{{\text{H}}_2}{\text{O}} + \Delta \]
C. \[{\text{2N}}{{\text{H}}_3} + 5{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}{\text{2NO}} + 6{{\text{H}}_2}{\text{O}} + \Delta \]
D. \[4{\text{N}}{{\text{H}}_3} + 4{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}4{\text{NO}} + 4{{\text{H}}_2}{\text{O}} + \Delta \]

Answer 1

Hint: Balancing chemical equations is based on the law of conservation of mass. The sum of the masses of the products is always the same as the sum of the masses of the reactants. It also states that mass is neither created nor destroyed in any ordinary chemical reaction.

Complete step by step answer:
A chemical equation is a simple way to describe a chemical reaction using symbols and formulas instead of words. During a chemical reaction, the atoms rearrange to form new bonds between atoms. The products formed in a chemical reaction have different properties from the reactants.
The steps involved in balancing chemical equations are:
Write the formula of each reactant and product.
Coefficients are added before elements so that the number of atoms in each element in reactants side is equal to that in the product side.
Subscripts cannot be changed.
Check the masses of reactants and products. It should be equal.
Now let’s consider each option.
A. \[4{\text{N}}{{\text{H}}_3} + 5{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}4{\text{NO}} + 6{{\text{H}}_2}{\text{O}} + \Delta \]
In these chemical reactions, the reactant side has four nitrogen, twelve hydrogen and ten oxygen atoms. The product side has four nitrogen, twelve hydrogen and ten oxygen. Thus the number of atoms are equal both in LHS and RHS. Thus it is balanced.
B. \[4{\text{N}}{{\text{H}}_3} + 3{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}4{\text{NO}} + 2{{\text{H}}_2}{\text{O}} + \Delta \]
Here, the number of hydrogen atoms is LHS and RHS is not equal. It differs by eight hydrogen in RHS, thus not said to be balanced.
C. \[{\text{2N}}{{\text{H}}_3} + 5{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}{\text{2NO}} + 6{{\text{H}}_2}{\text{O}} + \Delta \]
This equation is different by the number of hydrogen and oxygen atoms.
D. \[4{\text{N}}{{\text{H}}_3} + 4{{\text{O}}_2}\xrightarrow[{{\text{Pt}}}]{{{{800}^ \circ }{\text{C}}}}4{\text{NO}} + 4{{\text{H}}_2}{\text{O}} + \Delta \]
This is different by the number of hydrogen atoms.

So, the correct answer is Option A .

Note:
Oxidation of ammonia is carried out by Ostwald’s process in industries. It is carried out in a catalytic chamber. This chamber contains platinum gauze which serves as a catalyst. In primary oxidation, $95\% $ ammonia is converted into nitric oxide. Oxidation of ammonia is a reversible and exothermic reaction.