1. Convert millimoles to moles:
* 1 mole = 1000 millimoles
* 3.7 x 10^3 millimoles * (1 mole / 1000 millimoles) = 3.7 moles
2. Use Avogadro's number:
* Avogadro's number states that there are 6.022 x 10^23 atoms in one mole of any element.
3. Calculate the number of Cu atoms:
* 3.7 moles Cu * (6.022 x 10^23 atoms / 1 mole Cu) = 2.23 x 10^24 Cu atoms
Therefore, there are approximately 2.23 x 10^24 Cu atoms in 3.7 x 10^3 millimoles of copper.
