HCl (hydrochloric acid) is a strong acid; its ions completely dissociate when placed in solution. HF (hydrofluoric acid) is a weak acid; its ions do not completely dissociate in solution. Which one is a stronger electrolyte?

The stronger electrolyte is the HCl

Explanation:

Stronger electrolyte are the ones, that in water, completely dissociates.

HCl (aq) → H⁺ (aq) + Cl⁻ (aq)

HCl (aq) + H₂O (l) → H₃O⁺ (aq) + Cl⁻ (aq)

Both are acids, they bring protons to medium but the hydrochloric completely dissociates.

HF (aq) + H₂O (l) ⇄ H₃O⁺ (aq) + F⁻ (aq) Ka

In the dissociation of weak electrolytes, they ionize but at the same time they bond again, so the reaction is always kept in equilibrium.