Final answer:
The different conductance of ions in a solution, when cations and anions cannot be isolated, can be calculated using Kohlrausch's Law, which is based on the independent movement and contribution of each ion to the total conductivity.
Step-by-step explanation:
Understanding Conductance in Solutions
To figure out the different conductance of ions when we cannot isolate cations and anions, the most appropriate method is Kohlrausch's Law. Kohlrausch's Law of independent ionic mobility states that each ion contributes to the total conductivity of the solution in proportion to its concentration and its ionic conductance. This means that we can determine the conductance of individual ions in a mixture by knowing their individual contributions. When electrolytes dissolve in water, they split into cations and anions that move freely, carrying electrical current. The concentration of these ions affects the solution's overall conductance, which can be measured quantitatively by electrical current flow or qualitatively by observing changes such as brightness of a light bulb. Other methods such as measuring the temperature, altering the concentration, or observing color change of the solution are not as effective or direct in determining individual ion conductance as Kohlrausch's Law.