How many aluminum atoms are present in 3.78 g of aluminum (Al)? (Atomic mass of Al = 26.98 g/mol)

• A. 8.46 × 10^{22} atoms
• B. 1.41 × 10^{22} atoms
• C. 6.02 × 10^{23} atoms
• D. 2.53 × 10^{23} atoms

Answer: (A)

Verified step by step guidance

1. Identify the given information: mass of aluminum (Al) is 3.78 g, and the atomic mass of Al is 26.98 g/mol.
2. Calculate the number of moles of aluminum using the formula: \(\text{moles of Al} = \frac{\text{mass of Al}}{\text{atomic mass of Al}} = \frac{3.78}{26.98}\).
3. Recall that one mole of any substance contains Avogadro's number of atoms, which is \$6.022 \times 10^{23}$ atoms/mol.
4. Calculate the number of aluminum atoms by multiplying the moles of Al by Avogadro's number: \(\text{number of atoms} = \text{moles of Al} \times 6.022 \times 10^{23}\).
5. Express the final answer in scientific notation to match the format of the given options.