7. Activity and the Systematic Treatment of Equilibrium
Ionic Strength of Soluble Salts
Multiple Choice
Calculate the ionic strength for the following ionic compound.
0.04 M SnO2
A
0.40
B
0.48
C
0.12
D
0.96
E
0.24
Verified step by step guidance1
Identify the ions present in the compound SnO2. Tin(IV) oxide dissociates into Sn^{4+} and O^{2-} ions in solution.
Determine the concentration of each ion in the solution. Given that the concentration of SnO2 is 0.04 M, the concentration of Sn^{4+} ions is 0.04 M, and the concentration of O^{2-} ions is 0.08 M (since each SnO2 produces two O^{2-} ions).
Use the formula for ionic strength: I = \(\frac{1}{2}\) \(\sum\) c_i z_i^2, where c_i is the concentration of each ion and z_i is the charge of each ion.
Substitute the concentrations and charges into the formula: I = \(\frac{1}{2}\) [(0.04)(4)^2 + (0.08)(2)^2].
Calculate the ionic strength by evaluating the expression, ensuring to square the charges and multiply by the respective concentrations before summing and dividing by 2.
