Calculate the correct number of moles AND formula units in 7.3 x 10–3 g of CaSO4. Avogadro's number is 6.022 x 1023.

Step 1: Calculate the molar mass of CaSO4

The molar mass of CaSO4 is calculated by adding the molar masses of each element in the compound.

Calcium (Ca) = 40.08 g/mol Sulfur (S) = 32.06 g/mol Oxygen (O) = 16.00 g/mol * 4 = 64.00 g/mol

So, the molar mass of CaSO4 = 40.08 g/mol + 32.06 g/mol + 64.00 g/mol = 136.14 g/mol

Step 2: Calculate the number of moles

The number of moles is calculated by dividing the mass of the substance by its molar mass.

Number of moles = mass / molar mass = 7.3 x 10^-3 g / 136.14 g/mol = 5.36 x 10^-5 mol

Step 3: Calculate the number of formula units

The number of formula units is calculated by multiplying the number of moles by Avogadro's number.

Number of formula units = number of moles * Avogadro's number = 5.36 x 10^-5 mol * 6.022 x 10^23 = 3.23 x 10^19 formula units

So, there are 5.36 x 10^-5 moles and 3.23 x 10^19 formula units in 7.3 x 10^-3 g of CaSO4.