Explain why HCl can be a strong electrolyte, but a dilute HCl solution can be a poor conductor?

Because as the concentration is diminished, the capacity to transfer electricity is diminished as well.

Explanation:

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In this case, since electrolytes are substances that are able to conduct the electricity in aqueous media (solutions in which water is the the solvent) because they have the capacity to form ions with both positive and negative charges, due to the fact that HCl is a strong acid, we notice it is fully ionized in solution and therefore it is a strong electrolyte. However, when the concentration is diminished, we can notice that strength is diminished as well because less ions will have the capacity to transfer the electricity and therefore it'd become a poor conductor or weak electrolyte.

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