The ki melting point is the temperature at which potassium iodide, a white crystalline salt with chemical formula KI, melts. It is a common ingredient in the processing of iodine for medical and photographic purposes, but can also be found in a variety of other applications.
KI is formed when the elements potassium (K+) and iodine (I+) react with one another in a reaction that creates an extended lattice of alternating K1+ and I1+ ions. This is an unusual ionic bond because both of the cations are weakly electrostatically attracted to one another, so their centers of charge have the largest distance of separation.
Potassium iodide is often used to produce elemental iodine by heating in air or by standing in moist air. It is also a common component in radioactive decay reactions.
How to Prepare KI
In order to make potassium iodide, the two elements are first mixed together in an alkaline solution. This solution is then boiled down and filtered. Once the filtrate is concentrated, it is set aside to crystallize.
Why do Crystals Have Sharp Melting Points?
When crystals have regular, symmetrical atom arrangements throughout their lattice, they tend to have very sharp, well-defined melting points. This is because they have the same number and type of neighbors, creating uniform local environments.
However, short range solids do not have the same regularity and symmetry. They do not have a crystal lattice that is arranged in the same manner, which causes them to have less-defined melting points.