Question

Why is ferric chloride preferred over potassium chloride in case of a cut leading to bleeding?

Answer 1

A compound with high coagulation efficiency is preferred to prevent bleeding. Coagulant efficiency is directly proportional to the valency of the metal. Thus a metal with higher valency is preferred.

Complete step by step answer:
We are given to find the reason for why ferric chloride is preferred over potassium chloride in case of a cut leading to bleeding.
Ferric chloride is an inorganic compound which is soluble in water and non-combustible. The valency of ferric ion is +3. The chemical formula of ferric chloride is $FeC{l_3}$. The valency of ferric ion is 3 thus it requires three chlorine atoms in ferric chloride.
Potassium chloride is a metal halide salt which is an odorless white crystalline substance. The valency of potassium ion is +1. The chemical formula of Potassium chloride is $KCl$, to balance the +1 charge it bonds with only one chlorine atom.
As we can see the valency of ferric ion is greater than potassium ion.
Valency is directly proportional to the coagulation efficiency, which means it has high coagulant properties.
That is why ferric chloride is preferred over potassium chloride to prevent bleeding.

Additional Information: Ferric chloride is more compatible with skin than potassium chloride and does not cause any irritation when applied over the cut.

Note:
The bond angle in a linear molecule is 180 degrees, in a symmetrical tetrahedral molecule it is 90 degrees and in planar molecules, it is 120 degrees. The dipole moment is a vector quantity, therefore it has a direction. So in a linear molecule if one dipole moment is positive then the other will be negative thus the net dipole moment is zero.