3. Copper is commonly used to fabricate electrical wire. How many copper atoms are in 5.00 g of copper wire? (AM=63.55 g/mol)
To calculate the number of copper atoms in 5.00 g of copper wire, we first need to convert the mass of copper wire into moles.
1. Calculate the number of moles of copper in 5.00 g using the molar mass of copper:
Molar mass of copper (Cu) = 63.55 g/mol
Number of moles = Mass / Molar mass
Number of moles = 5.00 g / 63.55 g/mol
Number of moles = 0.0787 moles
2. Use Avogadro's number to convert moles to number of atoms:
1 mole of copper atoms = 6.022 x 10^23 atoms
Number of copper atoms = Number of moles x Avogadro's number
Number of copper atoms = 0.0787 moles x 6.022 x 10^23 atoms/mole
Number of copper atoms = 4.74 x 10^22 atoms
Therefore, there are approximately 4.74 x 10^22 copper atoms in 5.00 g of copper wire.