Question

Answer the following question:

A catalyst used in manufacture of nitric acid by Ostwald 's process.

Answer 1

Ostwald dilution law

• This law is just valid for the weak electrolytes and it completely fails for strong electrolytes because the strong electrolytes are completely ionized in the solution and then it results in a decrease in the value of the dissociation constant K with dilution.
• Simply, we can say that on dilution the degree of ionization increases. Thus, the degree of dissociation of the weak electrolyte is proportional to the square root of dilution.

Weak electrolytes: Weak electrolytes are the substances that dissociate partial in nature. For example- Acetic acid $\left({\mathrm{CH}}_3\mathrm{COOH}\right)$ undergoes partial dissociation to some amount of acetate ions $\left({\mathrm{CH}}_3{\mathrm{COO}}^{-}\right)$ and hydrogen $\left({\mathrm{H}}^{+}\right)$ ions.

Strong electrolytes: Strong electrolytes are the substances that can dissociate completely in their ionic solution. For example- In aqueous solution of $\left(\mathrm{NaCl}\right)$,it completely ionizes into $\left({\mathrm{Na}}^{+}\right)$ ions and $\left({\mathrm{Cl}}^{-}\right)$ ions.

• In Ostwald's process, Nitric acid$\left({\mathrm{HNO}}_3\right)$ is prepared from Ammonia$\left({\mathrm{NH}}_3\right)$.
• A catalyst used in manufacture of Nitric acid $\left({\mathrm{HNO}}_3\right)$ from Ammonia $\left({\mathrm{NH}}_3\right)$ is Platinum $\left(\mathrm{Pt}\right)$.