Let's solve the problem step by step as you requested. ### Step 1: Write Down the Given Data - Given mass of oxygen: **3.210 g** - Average atomic mass of oxygen: **16.00 g/mol** **Explanation:** We are given the total mass of oxygen and the atomic mass per mole. We need to find how many moles are in the sample. --- ### Step 2: Use the Formula to Find Moles The formula is: **Moles = Mass (g) / Molar Mass (g/mol)** Plug in the values: Moles = 3.210 g / 16.00 g/mol = **0.201 moles** **Explanation:** This calculation gives the number of moles of oxygen atoms in the sample. --- ### Step 3: Select the Correct Answer Look for the answer "0.201 moles O" among the provided options. **Explanation:** Based on the calculation, "0.201 moles O" is the correct answer. --- ## Final Answer: **0.201 moles O**

The concept used in solving this problem is the fundamental relationship between mass, molar mass, and moles. Specifically, it involves dividing the given mass of a substance by its molar mass to determine the number of moles. This concept is based on the molar mass being the mass of one mole of atoms or molecules, allowing conversion between grams and moles.