To calculate the mass of four atoms of copper in grams, you need to know the atomic weight of copper and use Avogadro's number. The atomic weight of copper (Cu) is approximately 63.55 atomic mass units. Avogadro's number, denoted as NA, is approximately 6.022 × 10^23 atoms per mole.
First, we calculate the molar mass of copper: Molar mass of copper = atomic weight of copper = 63.55 g/mol
Next, we calculate the number of moles in four atoms of copper: Number of moles = 4 atoms / NA = 4 / (6.022 × 10^23 mol-1)
Finally, we can calculate the mass using the molar mass and number of moles: Mass = Number of moles × Molar mass = (4 / (6.022 × 10^23)) × 63.55 g/mol
Evaluating this expression will give you the mass of four atoms of copper in grams.