A copper wire 81.9 cm long and 1.10 mm in diameter has a mass of 6.43 g.
(a) Find the number of electrons in the wire. (Copper has an atomic number of 29; that is, there are 29 protons in the Copper atom. Copper's atomic mass is 63.5.)
how many electrons:
(b) There is one free electron per atom in copper. Find the number of free electrons in the wire.
how many electrons :