## 3.21 Ground state

Vanessa Romero-Campos 2B
Posts: 39
Joined: Fri Sep 25, 2015 3:00 am

### 3.21 Ground state

Give the ground-state electron configuration and number of unpaired electrons expected for Ag+

I understand that the configuration is [Kr]4d10, but I don't understand why it's not Palladium which is also 4d10. They're both similar. Is either one correct or why is it not Palladium?

JasmineAlberto4J
Posts: 73
Joined: Fri Sep 25, 2015 3:00 am

### Re: 3.21 Ground state

Though the electron configuration might be the same, you must remember that a palladium atom an a Ag+ cation are two different things. When an Ag atom becomes an Ag+ cation, it loses an electron and consequently has the same number of valence electrons as a palladium atom but it doesn't become a palladium atom.

Chem_Mod
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### Re: 3.21 Ground state

4d10 refers to the silver ion's electron configuration, but even when the atom ionizes, the number of protons remains the same. Palladium has 46 protons and silver in its ionized and non-ionized state has 47 protons.

Christian Hessenauer 2A
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Joined: Fri Sep 25, 2015 3:00 am

### Re: 3.21 Ground state

When figuring out if one of the elements has paired or unpaired electrons you look at the valence electrons, correct? Then when the ion is positive or negative it will either add or subtract electrons from the atom. However, I still do not exactly know how to find out if the electrons are paired or not. What is the best way to figure that out?

Ritika Saranath 3I
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Joined: Fri Sep 25, 2015 3:00 am

### Re: 3.21 Ground state

If the molecule has an odd number of electrons (for example, NO2, nitrogen dioxide, has 17 electrons), then one of the electrons will be unpaired, and the molecule is a radical. If the molecule has an even number of electrons (for example, NO2-, nitrite ion, has 18 electrons), then all of the electrons are paired.
Last edited by Ritika Saranath 3I on Tue Oct 27, 2015 8:29 pm, edited 1 time in total.

JasmineAlberto4J
Posts: 73
Joined: Fri Sep 25, 2015 3:00 am

### Re: 3.21 Ground state

Christian Hessenauer 1C wrote:When figuring out if one of the elements has paired or unpaired electrons you look at the valence electrons, correct? Then when the ion is positive or negative it will either add or subtract electrons from the atom. However, I still do not exactly know how to find out if the electrons are paired or not. What is the best way to figure that out?

To figure out if there are unpaired electrons you look at the each orbital and picture the way they each orbital is filled. for example you know that the p orbital takes 6 electrons and if you have a configuration like [Ne]3s^2 3p^5 you there is one unpaired electron in the P
orbital
3p || || |
3s ||
similarly if if you have something like [Ne]3s^2 3p^4 there are two unpaired electrons in the p orbital
3p || | |
3s ||
hope this makes sense
P.S, these | are my attempt at writing an e- configuration where (||)represents a pair of a spin up and down and (|)represents a spin up