1. Write the Balanced Chemical Equation:

The reaction between potassium (K) and oxygen gas (O₂) produces potassium chloride (KCl):

4K + O₂ → 2K₂O

2. Determine the Mole Ratio:

From the balanced equation, we see that 4 moles of potassium react with 1 mole of oxygen to produce 2 moles of potassium oxide.

3. Calculate Moles of Potassium:

* Molar mass of potassium (K) = 39.10 g/mol

* Moles of potassium = (2.50 g) / (39.10 g/mol) = 0.0639 mol

4. Calculate Moles of Potassium Oxide:

* Using the mole ratio from the balanced equation: 0.0639 mol K * (2 mol K₂O / 4 mol K) = 0.0320 mol K₂O

5. Calculate Mass of Potassium Oxide:

* Molar mass of potassium oxide (K₂O) = 94.20 g/mol

* Mass of potassium oxide = (0.0320 mol) * (94.20 g/mol) = 3.01 g

Therefore, the mass of potassium oxide produced when 2.50 g of potassium reacts with oxygen gas is approximately 3.01 g.