What is the Lewis dot structure for Br2CNH?
The Correct Answer and Explanation is:
The Lewis dot structure for Br2CNH can be drawn by following these steps:
Step 1: Count the Valence Electrons
- Br (Bromine) is a halogen and has 7 valence electrons. Since there are two bromine atoms, that gives a total of 14 valence electrons.
- C (Carbon) is in group 14 and has 4 valence electrons.
- N (Nitrogen) is in group 15 and has 5 valence electrons.
- H (Hydrogen) has 1 valence electron.
Total valence electrons:
14 (from Br) + 4 (from C) + 5 (from N) + 1 (from H) = 24 valence electrons.
Step 2: Draw a Skeleton Structure
Place the atoms in the structure, with carbon (C) as the central atom since it typically forms the most bonds. The atoms will be connected as follows: Br – C – N – H. Both bromine atoms are single-bonded to carbon.
Step 3: Distribute Electrons
Each single bond between atoms represents 2 electrons. We have 3 bonds in the structure:
- 2 electrons for the Br – C bond.
- 2 electrons for the C – N bond.
- 2 electrons for the N – H bond.
This uses up 6 electrons (3 bonds × 2 electrons).
Step 4: Complete the Octet (or duet) Rule
- The bromine atoms (Br) will each have 6 electrons left after the bonding, so place 6 electrons around each Br as lone pairs. This gives each Br a complete octet.
- The carbon atom has 2 electrons from the single bonds and needs 6 more electrons to complete its octet. These 6 electrons will come from the lone pairs around the nitrogen atom (N). Carbon will form a double bond with nitrogen, leaving nitrogen with a lone pair to satisfy its octet.
- The nitrogen atom has 2 electrons from the C-N double bond, 2 electrons from the N-H single bond, and 2 electrons from its lone pair to complete its octet.
- The hydrogen atom has only 1 bond and completes its duet.
Step 5: Check the Structure
- Each atom should have the correct number of electrons around it: carbon has 8 electrons, nitrogen has 8 electrons, bromine has 8 electrons (from the 2 lone pairs plus 2 electrons from the bond), and hydrogen has 2 electrons.
- This structure should satisfy the octet rule for the atoms involved, except for hydrogen, which follows the duet rule.
Final Structure:
mathematicaCopyEdit Br
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Br-C=N-H
This structure correctly represents Br2CNH, with all atoms satisfying their valence electron requirements.
