How many moles of gold, Au, would have the same number of atoms as 84.0 g of silver, Ag?

Step 1: Determine the molar mass of silver (Ag). From the periodic table, the molar mass of Ag is approximately 107.87 g/mol.

Step 2: Calculate the number of moles of silver (Ag) in 84.0 g. Use the formula:

Number of moles = mass (g) / molar mass (g/mol)

Number of moles of Ag = 84.0 g / 107.87 g/mol = 0.778 moles

Step 3: The number of moles of gold (Au) that would have the same number of atoms as 0.778 moles of silver is also 0.778 moles (since 1 mole of any substance contains the same number of entities, Avogadro's number, 6.022 x 10^23).

So, 0.778 moles of gold (Au) would have the same number of atoms as 84.0 g of silver (Ag).