Answer to Question #70811 in General Chemistry for Jalyn

Question

When mixing the ionic solution pairs, is the quantity of each solution added to the test tube important? Why or why not?

Predict water solubility of following compounds: RbCl, NH4NO3, PBS, BaSO4, AgBr

Answer 1

1) The quantity of each solution is important The ionic strength of a solution is a
measure of the concentration of ions in that solution. Ionic compounds, when dissolved in
water, dissociate into ions. The total electrolyte concentration in solution will affect important
properties such as the dissociation constant or the solubility of different salts. Media of high
ionic strength are used in stability constant determination in order to minimize changes, during
a titration, in the activity quotient of solutes at lower concentrations.
2) Rule 1. Compounds containing an ion with a +1 or -1 ion are normally soluble.
Exceptions (Insoluble): Ag + with halogens
According rule 1: RbCl is soluble (Rb + and Cl - ), NH 4 NO 3 is soluble (NH 4 + and NO 3 - )
AgBr is insoluble (exception)
Rule 2. Compounds containing ions with a -2 charge are normally not soluble
Exceptions (Soluble): Sulfates (Insoluble only if combined with Pb, Hg, Ca, Sr, or Ba)
According rule 2: PbS is insoluble (S 2- ), BaSO 4 is soluble (exception – sulfate combined
with Ba)