Answer:
7.88 x 10²² formula units CuCl₂
Explanation:
To find the amount of formula units, you need to (1) convert grams to moles (via the molar mass) and then (2) convert moles to formula units (via Avogadro's Number). It is important to arrange the conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to match the sig figs of the given value.
Molar Mass (CuCl₂): 134.45 g/mol
Avogadro's Number:
6.022 x 10²³ formula units = 1 mole
17.6 g CuCl₂ 1 mole 6.022 x 10²³ formula units
-------------------- x ----------------- x ------------------------------------------ =
134.45 g 1 mole
= 7.88 x 10²² formula units CuCl₂
