Which of the following electron configurations correspond to an excited state? Identify the atoms and write the ground-state electron configuration where appropriate. If the configuration is a noble gas, enter the noble gas in brackets, for example [Ne] for F -. If the configuration given corresponds to a ground state electron configuration, say: "ground state"

(a) 1s2 2s2 3p1
element?

electron configuration?

(b) 1s2 2s2 2p6
element?

electron configuration?

(c) 1s2 2s2 2p4 3s1
element?

electron configuration?

(d) [Ar]4s2 3d5 4p1
element?

electron configuration?

How many unpaired electrons are present in each of these species?

(a) 1s2 2s2 3p1?

ground-state?

(b) 1s2 2s2 2p6?

ground-state?

(c) 1s2 2s2 2p4 3s1?

ground-state?

(d) [Ar]4s2 3d5 4p1?

ground-state?

The ground states are

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 etc. If a higher level is filled BEFORE all of the lower levels are filled that makes it an excited atom.
a) is an excited B atom. The ground state is
1s2 2s2 2p1

b)I think the problem is a little confusing. b) could be F^- or ground state of Ne. Ground state if F^- is
1s2 2s2 2p5
Ground state if Ne is [Ne]

great thanks and for the second part i can look at the orbital diagrams' arrows right?

(a) Element: Phosphorus

Excited state electron configuration: 1s2 2s2 3p1
Ground-state electron configuration: 1s2 2s2 2p6 3s2 3p3

(b) Element: Neon
Excited state electron configuration: 1s2 2s2 2p6
Ground-state electron configuration: [Ne]

(c) Element: Boron
Excited state electron configuration: 1s2 2s2 2p4 3s1
Ground-state electron configuration: 1s2 2s2 2p1

(d) Element: Bromine
Excited state electron configuration: [Ar]4s2 3d5 4p1
Ground-state electron configuration: [Ar]4s2 3d10 4p5

Number of unpaired electrons in each species:

(a) 1 unpaired electron
(b) 0 unpaired electrons
(c) 1 unpaired electron
(d) 1 unpaired electron

(a) The electron configuration 1s2 2s2 3p1 corresponds to an excited state.

- Element: The element with this electron configuration is aluminum (Al).
- Ground-state electron configuration: The ground-state electron configuration of aluminum is [Ne] 3s2 3p1.

(b) The electron configuration 1s2 2s2 2p6 corresponds to the ground state.

- Element: The element with this electron configuration is neon (Ne).

(c) The electron configuration 1s2 2s2 2p4 3s1 corresponds to an excited state.

- Element: The element with this electron configuration is sulfur (S).
- Ground-state electron configuration: The ground-state electron configuration of sulfur is [Ne] 3s2 3p4.

(d) The electron configuration [Ar] 4s2 3d5 4p1 corresponds to the ground state.

- Element: The element with this electron configuration is iodine (I).

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The number of unpaired electrons in each species is determined by the number of electrons with parallel spins (up or down) in the electron configuration.

(a) 1s2 2s2 3p1:
- Ground state: There is one unpaired electron.
- Excited state: There is one unpaired electron.

(b) 1s2 2s2 2p6:
- Ground state: There are no unpaired electrons.

(c) 1s2 2s2 2p4 3s1:
- Ground state: There is one unpaired electron.
- Excited state: There is one unpaired electron.

(d) [Ar] 4s2 3d5 4p1:
- Ground state: There is one unpaired electron.

To determine which electron configurations correspond to excited states, we need to compare them to the ground state configurations for the respective elements.

(a) 1s2 2s2 3p1: This electron configuration corresponds to an excited state because it has an electron in the 3p orbital, which is higher in energy than the 2p orbital. The element corresponding to this configuration is silicon (Si). The ground-state electron configuration for silicon is 1s2 2s2 2p6 3s2 3p2.

(b) 1s2 2s2 2p6: This electron configuration corresponds to the ground state because all the orbitals up to the 2p orbital are filled. The element corresponding to this configuration is neon (Ne).

(c) 1s2 2s2 2p4 3s1: This electron configuration corresponds to an excited state because it has an electron in the 3s orbital, which is higher in energy than the 2p orbital. The element corresponding to this configuration is boron (B). The ground-state electron configuration for boron is 1s2 2s2 2p1.

(d) [Ar]4s2 3d5 4p1: This electron configuration corresponds to an excited state because it has electrons in the 3d and 4p orbitals, which are higher in energy than the 4s orbital. The element corresponding to this configuration is technetium (Tc). The ground-state electron configuration for technetium is [Kr]5s2 4d5.

Now let's determine the number of unpaired electrons in each of these species:

(a) 1s2 2s2 3p1: This configuration has 1 unpaired electron.

(b) 1s2 2s2 2p6: This configuration has 0 unpaired electrons.

(c) 1s2 2s2 2p4 3s1: This configuration has 1 unpaired electron.

(d) [Ar]4s2 3d5 4p1: This configuration has 4 unpaired electrons.