Answer:
12.8 moles of potassium
Explanation:
449 g/39.10 g = 12.76 moles
First, you divide 449 g of potassium by its molar mass which is 39.10 g. Then you will get your answer, but you need to round it to 3 numbers because of Sig Figs, which makes it 12.8 moles.