Question

How do the impurities present in the electrolyte affect the conductivity?

Short answer

Answer: Impurities in an electrolyte can affect its conductivity by altering the concentration, charges, and mobilities of the ions. They can either dilute the electrolyte, reducing the concentration of ions and thereby decreasing conductivity, or interact with the ions, forming complexes that result in changed ion mobilities and affecting conductivity either positively or negatively depending on the nature of the impurities.

Step-by-step solution

Define the conductivity of an electrolyte

The conductivity of an electrolyte is a measure of its ability to conduct an electric current. It depends on the concentration of ions, their charges, and their mobilities (speed at which they can move under the influence of an electric field).

Discuss factors affecting conductivity

For an electrolyte, the factors affecting its conductivity include the following: 1. Concentration of ions: Higher concentration of ions generally leads to higher conductivity, as there are more charge carriers available for the electric current. 2. Charges of the ions: Ions with higher charges contribute more to the conductivity than those with lower charges, as they can transmit a larger amount of electric charge. 3. Mobility of the ions: Ions with higher mobilities contribute more to the conductivity than those with lower mobilities, as they can move more quickly through the electrolyte under the influence of an electric field.

Explain how impurities influence the factors affecting conductivity

Impurities present in the electrolyte can affect its conductivity by altering one or more of the factors mentioned above. There are two main ways impurities can influence the conductivity: 1. Dilution: Impurities may dilute the electrolyte, reducing the concentration of ions, and thereby decreasing its conductivity. For instance, adding water to an electrolyte will generally lower its conductivity due to the dilution effect. 2. Interference with ion mobility: Some impurities may interact with the ions present in the electrolyte, forming weaker or stronger complexes that result in changed ion mobilities. For example, adding a substance that forms a complex with one of the ions in the electrolyte could hinder its mobility, leading to a reduced conductivity. Conversely, if an impurity enhances ion mobility, the conductivity may increase. In summary, the impurities present in an electrolyte can affect its conductivity by altering the concentration, charges, and mobilities of the ions. Depending on the nature of the impurities, the conductivity may either increase or decrease.