What factors influence the solubility of a salt with respect to the given diagram?

1 Answer
Oct 6, 2016

Answer:

#"Option 4"# is the best candidate; i.e. (b) is the strongest electrolyte.

Explanation:

#"Option 1"# is contraindicated. No data are conveyed with respect to solubility.

#"Option 2"# is contraindicated, by the very terms of the question. Why?

#"Option 3"# is again contraindicated, by the very terms of the question. Why?

And this leaves #"Option 4"# as the only horse running. We started with #AY_2#. In solution this speciated to give discrete particles of (arguably) #A^(2+)# and #2xxY^(-)#; of course the charge could have been the other way round.

In solution #"b"# there was no association between cation and anion. When a strong electrolyte dissolves in water it speciates to give its constituent ions. Solutions #"a"# and #"c"# still showed associated ions. Why?

Real examples of #"Option 4"# could include #CaCl_2#, and #Na_2SO_4#, i.e. consider the following equation representing their dissolution, are as follows:

#CaCl_2(s) rarr Ca^(2+) + 2Cl^-#

#Na_2SO_4(s) rarr 2Na^+ + SO_4^(2-)#

This is a good and hard question designed to make you really think. I certainly had to do so!