Which conversion factor should be used to convert 3 moles of magnesium (Mg) to grams?

• A. 6.022 × 10^{23} atoms Mg / 1 mol Mg
• B. 1 g Mg / 1 mol Mg
• C. 1 mol Mg / 24.31 g Mg
• D. 24.31 g Mg / 1 mol Mg

Answer: (D)

Verified step by step guidance

1. Identify the quantity you have and the quantity you want to find. Here, you have 3 moles of magnesium (Mg) and want to convert it to grams.
2. Recall that the molar mass of magnesium (Mg) is 24.31 grams per mole. This means 1 mole of Mg weighs 24.31 grams.
3. Choose the conversion factor that relates moles to grams correctly. Since you want grams from moles, the conversion factor should have grams in the numerator and moles in the denominator.
4. Write the conversion factor as \$24.31\ \text{g Mg} / 1\ \text{mol Mg}$, so when you multiply by moles, the mole units cancel out, leaving grams.
5. Set up the conversion: multiply the given moles of Mg by the conversion factor \(\left(3\ \text{mol Mg} \times \frac{24.31\ \text{g Mg}}{1\ \text{mol Mg}}\right)\) to find the mass in grams.