1E.25

GFolk_1D
Posts: 101
Joined: Fri Aug 09, 2019 12:15 am

1E.25

Give the notation for the valence-shell configuration (including the outermost d-electrons) of (a) the alkali metals (b) Group 15 elements (c) Group 5 transition metals (d) the "coinage" metals (Cu, Ag, Au)

MAC 4G
Posts: 121
Joined: Wed Sep 18, 2019 12:16 am

Re: 1E.25

(a) The alkali metals are all the metals in Group 1A, belong in the s-block, and have 1 valence electron each. Therefore, depending on which shell the element is in, the configuration will be ns^1.

(b) Group 15 elements are in the p-block with 15 valence electrons each, 2 in the s sublevel, 10 in the d sublevel, 3 in the p sublevel. The configuration should be (n-1)d^10ns^2np^3.

(c) Group 5 transition metals are in the d block with each element having 2 valence electrons in the s sublevel and 3 in the d sublevel. The configuration should be (n-1)d^3ns^2.

(d) Cu, Ag, and Au belong to Group 11 and are in the d-block. They all have 1 in the s sublevel and 10 in the d sublevel because of the exception that a completely full or half full d sub-level is more stable than a partially filled d sub-level. An electron from the 4s orbital is transferred to the 3d orbital. So, the configuration is then (n-1)d^10ns^1.

Malia Shitabata 1F
Posts: 127
Joined: Sat Aug 17, 2019 12:17 am

Re: 1E.25

MAC 1G wrote:(a) The alkali metals are all the metals in Group 1A, belong in the s-block, and have 1 valence electron each. Therefore, depending on which shell the element is in, the configuration will be ns^1.

(b) Group 15 elements are in the p-block with 15 valence electrons each, 2 in the s sublevel, 10 in the d sublevel, 3 in the p sublevel. The configuration should be (n-1)d^10ns^2np^3.

(c) Group 5 transition metals are in the d block with each element having 2 valence electrons in the s sublevel and 3 in the d sublevel. The configuration should be (n-1)d^3ns^2.

(d) Cu, Ag, and Au belong to Group 11 and are in the d-block. They all have 1 in the s sublevel and 10 in the d sublevel because of the exception that a completely full or half full d sub-level is more stable than a partially filled d sub-level. An electron from the 4s orbital is transferred to the 3d orbital. So, the configuration is then (n-1)d^10ns^1.

For parts b through d why does the d orbital come before the s and p orbital if we're talking about all of Group 15 collectively? Shouldn't it go after?

MAC 4G
Posts: 121
Joined: Wed Sep 18, 2019 12:16 am

Re: 1E.25

I also realized that there were some mistakes in my answers.

a)ns^1
b)ns^2np^3
c)(n-1)d^5ns^2
d)(n-1)d^10ns^1

I believe that the d orbital comes first being that orbitals are filled in the lower energy orbitals first, then fill higher energy orbitals.

For instance, the 3d orbitals have a slightly higher energy than the 4s orbitals. So because the 4s orbitals has the lower energy, it gets filled first. When 3d orbitals are filled, 4s is no longer lower in energy. Hence electrons are lost from 4s orbital first, because electrons lost first will come from the highest energy level (furthest away from the nucleus), meaning it is less stable, and thus,will lose it's electron easier.