Answer:
2.14x10¹⁹ atoms of Cu were deposited
Step-by-step explanation:
The increased in mass of the glass slide is due the deposition of copper.
That means the mass of copper deposited is 2.26mg = 2.26x10⁻³g Cu
To know the copper atoms we need to convert this mass to moles of Cu using molar mass of copper (63.546g/mol), and these moles are converted to atoms using Avogadro's number (6.022x10²³ atoms = 1 mole)
Moles Cu:
2.26x10⁻³g Cu * (1 mol / 63.546g) = 3.556x10⁻⁵ moles Cu
Atoms Cu:
3.556x10⁻⁵ moles Cu * (6.022x10²³ atoms / 1 mole) =
2.14x10¹⁹ atoms of Cu were deposited