To determine how many moles are in 220 grams of carbon dioxide (CO₂), we need to use the concept of molar mass and the formula for calculating moles. Let's break this down step-by-step. ### Step 1: Understand the Concept of Moles Moles are a unit of measurement in chemistry that allows us to count particles (like atoms or molecules) in a substance. One mole of any substance contains Avogadro's number of particles, which is approximately \(6.022 \times 10^{23}\) particles. ### Step 2: Calculate the Molar Mass of Carbon Dioxide (CO₂) To find the number of moles in a given mass of a substance, we first need to know its molar mass. The molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). 1. **Identify the elements in CO₂**: - Carbon (C) - Oxygen (O) 2. **Find the atomic masses** (approximately): - Carbon (C): 12.01 g/mol - Oxygen (O): 16.00 g/mol 3. **Calculate the molar mass of CO₂**: - CO₂ has 1 carbon atom and 2 oxygen atoms. - Molar mass of CO₂ = (1 × 12.01 g/mol) + (2 × 16.00 g/mol) - Molar mass of CO₂ = 12.01 g/mol + 32.00 g/mol = 44.01 g/mol ### Step 3: Use the Molar Mass to Calculate Moles Now that we have the molar mass of CO₂, we can calculate the number of moles in 220 grams of CO₂ using the formula: \[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \] Substituting the values we have: \[ \text{Number of moles} = \frac{220 \text{ g}}{44.01 \text{ g/mol}} \approx 5.00 \text{ moles} \] ### Step 4: Analyze the Options Now, let's look at the options provided: - **A. 5** (This is the correct answer) - **B. 6** (This is incorrect; it overestimates the number of moles based on the given mass.) - **C. 3** (This is incorrect; it underestimates the number of moles significantly.) - **D. 4** (This is incorrect; it is also an underestimation of the number of moles.) ### Step 5: Conclusion The correct answer is **A. 5** moles of carbon dioxide in 220 grams. ### Revision Summary - Moles are a way to count particles in chemistry, using Avogadro's number. - The molar mass of CO₂ is calculated as 44.01 g/mol. - The number of moles can be calculated using the formula: \(\text{Number of moles} = \frac{\text{mass}}{\text{molar mass}}\). - For 220 g of CO₂, the calculation yields approximately 5 moles. This thorough understanding of moles and molar mass is crucial for solving similar problems in chemistry.