WAEC - Chemistry (2002 - No. 14)
The atomic number of chlorine is 17. What is the number of electrons in a chloride ion?
16
17
18
19
Explanation
Cl = 17 = 2, 8, 7.
Cl ion = Cl\(^-\) = 2, 8, 8 = 18.
Cl = 17 = 2, 8, 7.
Cl ion = Cl\(^-\) = 2, 8, 8 = 18.