What is the Lewis Structure of CoBr2? Please Explain Steps and Sharp of Valence Electrons Used to Find Solution.

The Lewis structure of CoBr₂ (Cobalt Bromide) can be determined by following a few essential steps. Here’s how you can find it:

1. Determine the Total Number of Valence Electrons:

   Cobalt (Co) is in group 9 of the periodic table and has 9 valence electrons. Bromine (Br) is in group 17 and has 7 valence electrons. Since there are two bromine atoms, we multiply the number of valence electrons for bromine by 2. Thus, the total valence electrons for CoBr₂ is:

   9 (for Co) + 2 × 7 (for Br) = 9 + 14 = 23 valence electrons.

2. Identify the Central Atom:

   The central atom in CoBr₂ will be cobalt (Co) because it is less electronegative than bromine.

3. Place Br Atoms Around Co:

   Now, we place the two bromine atoms on either side of the cobalt atom, creating a structure where Co is the central atom with Br atoms attached to it:

      Br
       |
      Co
       |
      Br

4. Create Bonds:

   Next, we need to form bonds between the cobalt and the bromine atoms. Since each bond consists of 2 electrons, we will use 2 electrons for each Co-Br bond. Therefore, with 2 bonds, we are using 4 out of the total 23 valence electrons:

   Total used = 4 electrons; Remaining = 23 – 4 = 19 electrons

5. Distribute Remaining Electrons:

   We now have 19 valence electrons left to distribute. We first fulfill the octet rule for the bromine atoms. Each bromine will need 6 more electrons (3 lone pairs) to complete their octets:

      Br : 3 lone pairs
       |
      Co
       |
      Br : 3 lone pairs

   This uses 12 electrons (6 for each Br) from our remaining 19 electrons.

   Total used = 4 + 12 = 16 electrons; Remaining = 19 – 12 = 3 electrons.

6. Check the Structure:

   Now we can place the remaining 3 electrons on the cobalt, making it have 3 additional electrons not participating in bonds. Therefore, cobalt will have 12 electrons around it, which can happen due to its ability to exceed the octet rule.

The final Lewis structure of CoBr₂ shows cobalt in the center with two bromine atoms bonded to it. Each bromine atom has 3 lone pairs, and cobalt has 3 electrons that are not in bonds, resulting in:

   Br : 3 lone pairs
    |
   Co :  3 lone pairs + 3 additional
    |
   Br : 3 lone pairs

This indicates cobalt has a coordination number of 2 with bromine, while each bromine completes its octet. Understanding these steps helps visualize how valence electrons are utilized in constructing the Lewis structure for CoBr₂.