An alloy consists of 6 atomic percent Pb and 94 atomic percent Sn. What is the weight percent of Pb in the alloy? (Atomic masses: Pb = 207.2 g/mol, Sn = 118.7 g/mol)

• A. 12.5%
• B. 6.0%
• C. 17.3%
• D. 24.6%

Answer: (D)

Verified step by step guidance

1. Identify the given data: the alloy contains 6 atomic percent Pb and 94 atomic percent Sn. Atomic masses are Pb = 207.2 g/mol and Sn = 118.7 g/mol.
2. Assume a total of 100 atoms in the alloy for simplicity. This means there are 6 atoms of Pb and 94 atoms of Sn.
3. Calculate the total mass of Pb and Sn in the alloy by multiplying the number of atoms by their respective atomic masses: mass of Pb = 6 atoms \times 207.2 g/mol, mass of Sn = 94 atoms \times 118.7 g/mol.
4. Find the total mass of the alloy by adding the mass of Pb and the mass of Sn together.
5. Calculate the weight percent of Pb using the formula: \(\text{weight \% Pb} = \left( \frac{\text{mass of Pb}}{\text{total mass of alloy}} \right) \times 100\).