How many molecules are present in 345 grams of carbon dioxide (CO_2)?

• A. 1.15 × 10^{25} molecules
• B. 4.73 × 10^{24} molecules
• C. 2.13 × 10^{24} molecules
• D. 6.02 × 10^{23} molecules

Answer: (B)

Verified step by step guidance

1. Identify the given quantity: 345 grams of carbon dioxide (CO\_2). Our goal is to find the number of molecules in this mass.
2. Calculate the molar mass of CO\_2 by adding the atomic masses of carbon and oxygen: Molar mass = (1 \times atomic mass of C) + (2 \times atomic mass of O). Use atomic masses approximately 12.01 g/mol for C and 16.00 g/mol for O.
3. Convert the given mass of CO\_2 to moles using the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}}\).
4. Use Avogadro's number, \$6.022 \times 10^{23}\( molecules/mol, to convert moles of CO\_2 to molecules: \)\text{number of molecules} = \text{moles} \times 6.022 \times 10^{23}$.
5. Perform the multiplication to find the total number of molecules in 345 grams of CO\_2.