Give the Frost Salts to Arcadia

Walkthrough
This quest begins when the Dragonborn asks the court wizard, Farengar Secret-Fire, if he is the only wizard in Whiterun. At that point, the mage mentions Arcadia and asks the Dragonborn to deliver some Frost Salts to her at her shop, Arcadia's Cauldron.

Give the Frost Salts to Arcadia
If the Dragonborn accepts, then it is a simple matter to bring the frost salts to Arcadia and collect the reward.

Bringe Frostsalze zu Arcadia