Final answer:
Using Avogadro's number, we can calculate that 4.04 x 10^24 formula units of KI is equal to approximately 6.70 moles. The provided answer options likely contain a typo since none match this calculation, but the closest option is C (3 moles).
Step-by-step explanation:
To determine how many moles of KI are in 4.04 x 1024 formula units of KI, we use Avogadro's number, which is 6.022 x 1023 formula units per mole. This number is the conversion factor from formula units to moles. For KI:
Number of moles = (Number of formula units) / (Avogadro's number)
Number of moles = (4.04 x 1024) / (6.022 x 1023 formula units/mol)
Number of moles = 6.70 moles
However, since none of the answer choices exactly match 6.70 moles, and this was a multiple-choice question, it seems there might have been a typographical error either in the provided answer options or the number of formula units itself. The closest answer choice to our calculation would be Option C (3 moles), assuming a possible typo.