How many valence electrons does zinc have?

1 Answer
Jun 17, 2015

Answer:

You take a look at its electron configuration.

Explanation:

Zinc is located in period 4, group 12 of the periodic table and has an atomic number equal to 30.

This means that neutral zinc atom has a total of 30 electrons surrounding its nucleus. To see how many of these electrons are valence electrons, write the electron configuration of a neutral zinc atom.

#"Zn": 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10#

or, if you use the noble gas shorthand notation

#"Zn": ["Ar"] 4s^2 3d^10#

Notice that the outermost shell, which for zinc is the fourth shell, #"n=4"#, has two electrons.

This means that zinc can lose the two electrons located in the 4s-orbital to be become the #Zn^(2+)# cation.

#"Zn"^(2+): ["Ar"] 3d^10#

Notice that the 3d-orbital is completely filled, which means that these electrons behave like core electrons and cannot be considered valence electrons.

Therefore, zinc has only 2 valence electrons, both located in the 4s-orbital.

http://wendtsworld.weebly.com/periodic-table-of-us.html