Q59E - Chemistry (OpenStax)

Question

Question: Which of the following has two unpaired electrons?

(a) Mg

(b) Si

(c) S

(d) Both Mg and S

(e) Both Si and S.

Step-by-Step Solution

Answer

   (e) both Si and S.

Step 1: determining if Mg has 2 unpaired electrons

 Using the electron configuration table, we can observe that Mg has 2 electrons in its valence shell. 

MG =

Hence, there is no unpaired electron.

Step 2: determining if Si has 2 unpaired electrons

Using the electron configuration table, we can observe that Si has 2 electrons in the 3p orbital. 

Hence, there are two unpaired electrons.

Step 3: determining if S has 2 unpaired electrons

Using the electron configuration table, we can observe that S has 4 electrons in the 3p orbital.

Hence, there are two unpaired electrons.