Video Transcript
You are given five acidic solutions in a lab experiment, and each acid exhibits a
different degree of dissociation, as seen in the table. Which acid has better electrical conductivity? Assume that their concentration is the same and that room temperature is
maintained.
Electrical conductivity is due to the movement of charged particles. In general, the more charged particles there are in a solution, the more electrically
conductive a solution will be.
In this question, we want to compare the electrical conductivity of different acidic
solutions. In solution, acids dissociate to form charged particles. Some acids dissociate to form ions more than others. We can compare how much different acids dissociate using the degree of
dissociation. The degree of dissociation, given the Greek letter 𝛼, is defined as the amount of a
substance that dissociates divided by the total amount of substance. 𝛼 is typically expressed in a range from zero to one. 𝛼 can also be expressed as a percentage. Either way, greater values indicate that more of the substance has dissociated into
ions.
We want to know which acid will have better electrical conductivity. We know that a higher concentration of charged particles will mean the acid is more
electrically conductive. The question tells us that the concentrations of all the acids are the same. So, the solution that has the most charged particles will be the one with the highest
degree of dissociation because a higher degree of dissociation means that more
charged particles are formed. If we compare the degrees of dissociation for the acids in this question, we can see
that the acid HX has the highest degree of dissociation. So the acid that has the best electrical conductivity is HX.
