Consider these two electron configurations for neutral atoms L and M.
L - 1s22s22p63s2
M - 1s22s22p63s13p1
What is the difference between atom L and atom M?
One of the 2p electrons in L has jumped to an excited state
One of the 3p electrons in L has jumped down to a lower energy state
One of the 3s electrons in M has jumped to an excited state
One of the 3p electrons in M has jumped down to a lower energy state

Question

Consider these two electron configurations for neutral atoms L and M.
L - 1s22s22p63s2
M - 1s22s22p63s13p1
What is the difference between atom L and atom M? 
One of the 2p electrons in L has jumped to an excited state
One of the 3p electrons in L has jumped down to a lower energy state
One of the 3s electrons in M has jumped to an excited state
One of the 3p electrons in M has jumped down to a lower energy state

bm717 · Answer

$$L-1s^22s^22p^63s^2$$
$$M-1s^22s^22p^63s^13p^1$$

bm717 · Answer

What do you think?

JT · Answer

I was thinking the last option

bm717 · Answer

I think that too, but you might need an expert opinion
@Vocaloid

nuts · Answer

well you both think wrong, clearly the S state is lower than the P state and what's going on here is the third option in that in M, one of the electrons has been excited from the s state to the p state.