Final answer:
To convert 200.0 g of FeCl2 to formula units, calculate the number of moles by dividing the mass by the molar mass of FeCl2 and then multiply by Avogadro's number to obtain approximately 9.496 × 10^23 formula units of FeCl2.
Step-by-step explanation:
To convert 200.0 g of FeCl2 to formula units of FeCl2, you must follow a few steps involving molar mass and Avogadro's number. First, find the molar mass of FeCl2, which is the sum of the atomic masses of iron (Fe) and chlorine (Cl). The atomic mass of Fe is approximately 55.85 amu, and each Cl has an atomic mass of approximately 35.45 amu. So, the molar mass of FeCl2 is (55.85 + (2 × 35.45)) = 126.75 g/mol. Next, you calculate the number of moles of FeCl2 by dividing the given mass by the molar mass:
moles FeCl2 = 200.0 g / 126.75 g/mol = 1.577 moles FeCl2.
Then, multiply the moles of FeCl2 by Avogadro's number, which is 6.022 × 10^23 formula units/mol, to find the number of formula units:
formula units FeCl2 = 1.577 moles × 6.022 × 10^23 formula units/mol = 9.496 × 10^23 formula units FeCl2.
Therefore, 200.0 g of FeCl2 is equivalent to approximately 9.496 × 10^23 formula units of FeCl2.