Which of the following electron configurations of neutral atoms represent excited states?
[Xe]6s^2 4f^1
[Ar]4s^2 3d^3
1s^2 2s^2 2p^6 3s^2 3p^6 3d^2
[Kr]5s^1 4d^5
2s^2
Which neutral atoms have the following electron configurations? Enter the name or symbol.
[Ar]4s^2 3d^3
[Kr]5s^1 4d^5
To determine which of the given electron configurations represent excited states, we need to compare them to the ground state electron configuration for each element.
The ground state electron configuration of an element represents the lowest energy arrangement of electrons in its neutral state. It follows a specific pattern based on the periodic table.
For the first question, we will analyze each option:
1. [Xe]6s^2 4f^1: This is an example of an excited state electron configuration. It is different from the ground state configuration of the element because there is an electron in the 4f orbital, which is not typical for this element (Xe).
2. [Ar]4s^2 3d^3: This configuration represents the ground state of an element. The noble gas configuration of argon ([Ar]) accounts for the complete filling of the 3p orbitals, and the subsequent electrons occupy the 4s and 3d orbitals.
3. 1s^2 2s^2 2p^6 3s^2 3p^6 3d^2: This configuration represents the ground state of an element. It follows the filling order based on the periodic table, starting with the lowest energy orbitals.
4. [Kr]5s^1 4d^5: This electron configuration represents an excited state. It differs from the ground state configuration of the element because there is an electron in the 4d orbital, which is not typical for this element (Kr).
5. 2s^2: This configuration does not represent an excited state. It corresponds to the ground state electron configuration of an element, specifically the helium ion with a +2 charge (He2+).
Therefore, the electron configurations that represent excited states are [Xe]6s^2 4f^1 and [Kr]5s^1 4d^5.
Moving on to the second question:
The given electron configuration is [Ar]4s^2 3d^3. To determine the element corresponding to this electron configuration, we need to identify the element that matches this electron arrangement.
The electron configuration [Ar]4s^2 3d^3 matches the ground state electron configuration of the element Titanium (Ti).
So, for the first question, the atom with the electron configuration [Ar]4s^2 3d^3 is Titanium (Ti).
For the second question, the atom with the electron configuration [Kr]5s^1 4d^5 is Iodine (I).
Please note that the electron configurations provided in the questions may represent either neutral atoms or ions with specific charges.
For the first question, the electron configuration [Xe]6s^2 4f^1 represents an excited state since the electron from the 6s orbital has been excited to the 4f orbital.
For the second question, the electron configuration [Ar]4s^2 3d^3 corresponds to the neutral atom of the element Chromium (Cr).
The electron configuration [Kr]5s^1 4d^5 corresponds to the neutral atom of the element Iodine (I).
I'll give you a hint for 1.
Look at the last one. It must be excited since the ground state would be 1s2 to start. Look at the one before that. It has 5s1 + others but 5s2 is the ground state. There may be others there.
#2. Count the electrons. For the first one I count 18 + 2 + 3 = 23. Which element is #23. That's V isn't it.