Question 9
the process by which the positive and negative ions of a crystalline solid separate in water is called
a)dissociation
b)ionization
c)saturation
d)solution

The process is A) dissociation.

In this process, the crystalline ions can be separated as well as split into smaller particles like radicals, ions, or atoms, generally in a reversible way.  

As an example, if an atom is dissolved in the water, a chemical bond that shares electron pairs among the atoms between a single hydrogen atom and electronegative atom is fragmented through heterolysis fission giving off a positive ion and a negative ion.

B: iron and nickel

Explanation:

I am sure of it because I learnt it in class :)