1. Determine the number of oxygen atoms per formula unit:

* The formula K₂Cr₂O₇ shows that there are 7 oxygen atoms per molecule of potassium dichromate.

2. Calculate the molar mass of oxygen:

* The molar mass of oxygen is 16.00 g/mol.

3. Calculate the total mass of oxygen in 2 moles of potassium dichromate:

* Step 1: Multiply the number of oxygen atoms per molecule by the number of moles of potassium dichromate: 7 oxygen atoms/molecule * 2 moles = 14 moles of oxygen atoms.

* Step 2: Multiply the moles of oxygen atoms by the molar mass of oxygen: 14 moles * 16.00 g/mol = 224 g

Therefore, there are 224 grams of oxygen in 2 moles of potassium dichromate.