Question

Which of the following is a reasonable ground-state electron configuration? a. 1s22s22p43s2 b. 1s21p62s22p6 c. 1s22s22p63s23p64s24d10 d. 1s22s22p63s23p64s23d5

Answer 1

start with a basic introduction to electron sublevels. "s" sublevels hold 2 electrons. "p" sublevels hold 6 electrons. "d" sublevels hold 10 electrons. "f" sublevels hold 14 electrons. Sublevels fill in the following order:

1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d....

i will show why 2 of your answers are wrong .
a. 1s2 2s2 2p4 3s2- wrong there are only 4 electrons in 2p shell
b. 1s2 1p6 2s2 2p6 - wrong no p sublevel l in first shell

get the idea?

Answer 2

no . b .. because it's completely filled with electrons in it's out most energy level

Answer 3

there in no p in first shell