Question

Silver tarnish is Ag₂S. When silver metal is tarnished, it is oxidized. If a bar of silver is covered with 8.1 g of tarnish, what amount of silver atoms was oxidized? Answer in units of mol.

Answer 1

To calculate the moles of silver atoms oxidized when a bar of silver is covered with 8.1 g of tarnish (Ag₂S), we can use the molar mass of Ag₂S. The moles of Ag₂S can then be converted to moles of silver atoms using the balanced equation. After calculations, we find that 0.0654 mol of silver atoms were oxidized.

Step-by-step explanation:

To determine the amount of silver atoms oxidized, we first need to calculate the moles of Ag₂S (tarnish) formed. From the given information, we know that the mass of tarnish is 8.1 g. Using the molar mass of Ag₂S (247.8 g/mol) and the formula mass relationship, we can calculate the moles of Ag₂S:

moles of Ag₂S = mass of Ag₂S / molar mass of Ag₂S

moles of Ag₂S = 8.1 g / 247.8 g/mol = 0.0327 mol Ag₂S

The balanced equation shows that 2 silver atoms are required to form 1 mole of Ag₂S. Therefore, the moles of silver atoms oxidized is:

moles of Ag atoms = 2 * moles of Ag₂S

moles of Ag atoms = 2 * 0.0327 mol = 0.0654 mol of Ag atoms