Final answer:
A mole of Ag (silver) atoms would have a higher mass than a mole of K (potassium) atoms because the molar mass of Ag is approximately 107.87 g/mol, which is greater than the molar mass of K at 39.10 g/mol.
Step-by-step explanation:
To determine which would have a higher mass, a mole of K atoms or a mole of Ag atoms, we need to compare their molar masses. Referring to the periodic table, the atomic mass of K (potassium) is approximately 39.10 amu, and thus has a molar mass of 39.10 g/mol. On the other hand, silver (Ag) has an atomic mass of roughly 107.87 amu, which means its molar mass is 107.87 g/mol. Since a mole of any element contains the same number of atoms (Avogadro's number, depicted by numeral value 6.022×10²³), the mole of Ag atoms would have a higher mass because Ag has a greater molar mass than K.