Question 1
How many Cu atoms are present in a 75.0 cm length of 20-gauge copper wire? A 20-gauge wire has a diameter of 0.03196 in. Copper's density is 8.92 g/cm
3.
◦ 1.31 × 10
21 ◦ 3.28 × 10
22 ◦ 8.08 × 10
21 ◦ 1.04 × 10
22 ◦ 2.08 × 10
22 Question 2
How many electrons are in a neutral atom of bromine-81?
◦ 1
◦ 35
◦ 36
◦ 81