## Number of Valence Electrons

Sarah Zhari 1D
Posts: 103
Joined: Sat Sep 14, 2019 12:16 am

### Number of Valence Electrons

If a question asks you to "give the number of valence electrons (including d electrons)" for manganese, how many valence electrons are there? I thought that the electron configuration of manganese is [Ar]3d5 4s2, therefore should the number of valence electrons be 2 or 7?

Shannon Asay 1C
Posts: 102
Joined: Fri Aug 09, 2019 12:16 am

### Re: Number of Valence Electrons

I believe it would have 7 valence electrons because you include the electrons from the d and s orbital.

SnehinRajkumar1L
Posts: 101
Joined: Thu Jul 11, 2019 12:15 am

### Re: Number of Valence Electrons

The number of valence electrons is 7 for manganese. It includes the 3d orbital electrons because the difference in energy between the 3d orbital and 4s is very small, so they essentially are in the same energy level. However, transition metals can have multiple valence states, so technically 2 or 7 can be right. But, since it asks you to include d orbitals, the answer should be 7.

Sartaj Bal 1J
Posts: 101
Joined: Thu Jul 25, 2019 12:17 am

### Re: Number of Valence Electrons

Transition metals can use their d electrons for bonding due to an incomplete d subshell. Therefore, a transition metal's valence electrons include the ns and (n-1)d electrons. In this case, Manganese would have 7 valence electrons.

Jenna Ortiguerra 4G
Posts: 50
Joined: Sat Aug 17, 2019 12:18 am

### Re: Number of Valence Electrons

There are 7 valence electrons in manganese, with 5 valence electrons coming from the 3d orbital (since the question asks you to include d electrons) and 2 valence electrons coming from the 4s orbital.

zfinn
Posts: 106
Joined: Fri Aug 30, 2019 12:16 am

### Re: Number of Valence Electrons

It would have 7 valence e- (from d and s), and would more readily loose e- from the 4s shell.

Return to “Electron Configurations for Multi-Electron Atoms”

### Who is online

Users browsing this forum: No registered users and 1 guest