Question

Why is it possible to separate the cobalt salt from the mixture (Iodine, sand), but not possible to separate the cobalt from the Chlorine in the Cobalt compound?

Answer 1

You can separet the salt, form other things, Iodine and sand, by physical means, using a mesh, separating the crystals one by one. The same way you can separate each color of skittles, all of these is beacause you know physical characteristics of each of the components of the mixture.

The problem of separating elements that are bonded each other is that the bond is at an imperceptible level and it requires a lot of energy, imagine, two atoms with a diameter of 1x10^-10m, it is completely impossible to see.

Using the same example, you can separate the skittles by color but you cannot separate their components (those written in the package).

In order to separeta Chlorine and Cobalt from the compound you need a chemical reaction.