Question

Give reasons for the following observations:

1. Leather gets hardened after tanning.
2. Lyophilic solution is more stable than lyophobic solution.
3. It is necessary to remove $CO$ when ammonia is prepared by Haber’s process.

Answer 1

‌We know that in the leather industry mutual coagulation takes place. For the second part of the question in lyophilic lyo means solvent and philic means having affinity for, on the other hand in lyophobic phobic means hating. Also, we know that Carbon monoxide promotes molybdenum in Haber’s process.

Complete step by step solution:

1. Leather gets hardened after tanning as we already know that mutual coagulation takes place. In the process of tanning two chemicals of opposite charges are coagulated. We know that animal hides of leather are colloidal in nature and are positively charged so it requires a negatively charged colloidal chemical to complete the process of coagulation. This is known as mutual coagulation. When positively charged particles are mixed with negatively charged particles, hardening of leather takes place.
2. So lyophobic solutions are the ones which are created simply by combining the substance with the medium for dispersion. These are not stable and on the other hand lyophilic solutions are the ones that are produced directly by mixing substances in an effective dispersion medium. These are very stable. Hence lyophilic solution is more stable as it is dependent on the result of two factors which are the presence of a charge and the solvation of colloid particles.
3. It is necessary to remove $CO$ when ammonia is obtained by Haber’s process because $CO$ acts as a poison for the catalyst which is used in the manufacturing of ammonia by Haber’s process. It acts as a poison for the catalyst iron and also for molybdenum because $CO$combines with iron catalyst and forms iron carbonyl $Fe{(CO)_3}$

Note: we know that a catalyst is a substance which increases the rate of the reaction hence when $CO$ combines with iron and molybdenum which in turn reduces the activity of the catalyst. Lyophilic solutions are also known as reversible solutions because the dispersion medium can be isolated from the colloid by evaporation.