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# Ostwald's process is a chemical process for making nitric acid $\text{HNO}_3$ by which of the following methods:

$\begin{array}{1 1}(a)\;Reduction\;of\;NH_3\\(b)\;Oxidation\;of\;NH_3\\(c)\;Hydrogenation\;of\;NH_3\\(d)\;Hydrolysis\;of\;NH_3\end{array}$

Answer: Oxidation of $\text{NH}_3$
Ammonia is converted to nitric acid in 2 stages. It is oxidized (in a sense "burnt") by heating with oxygen in the presence of a catalyst such as platinum with 10% rhodium, to form nitric oxide and water.
$4NH_3+5O_2\rightarrow 4NO+6H_2O$
Stage two encompasses two reactions and is carried out in an absorption apparatus containing water. Initially nitric oxide is oxidized again to yield nitrogen dioxide. This gas is then readily absorbed by the water, yielding the desired product (nitric acid, albeit in a dilute form), while reducing a portion of it back to nitric oxide.
$2NO+O_2\rightarrow 2NO_2$
$2NO_2+H_2O+(O)\rightarrow 2HNO_3$
edited Jul 14, 2014