How many moles are present in 4.9 \times 10^{23} molecules of CO_2?

• A. 8.1 moles
• B. 1.2 moles
• C. 0.81 moles
• D. 0.49 moles

Answer: (C)

Verified step by step guidance

1. Identify the given quantity: 4.9 \times 10^{23} molecules of CO_2.
2. Recall Avogadro's number, which is the number of molecules in one mole: 6.022 \times 10^{23} molecules/mole.
3. Set up the conversion from molecules to moles using the relationship: \(\text{moles} = \frac{\text{number of molecules}}{\text{Avogadro's number}}\).
4. Substitute the given values into the formula: \(\text{moles} = \frac{4.9 \times 10^{23}}{6.022 \times 10^{23}}\).
5. Perform the division to find the number of moles (do not calculate the final value here, just set up the expression).