The principal quantum number of the valence electrons in a atom of lead is
A. 2
B. 3
C. 4
D. 5
E. 6
2 answers
The principal quantum number corresponds to the number of the element's period. Lead is in the sixth period, so its quantum number is 6.
The energy level of the valence electrons of every element is the same as its period in the periodic table.
So in this case Lead = 6 (E.)
So in this case Lead = 6 (E.)