Question

question 1 (2 points)
how many electron groups are around the central atom in brf₃? (hint: draw the lewis structure before answering.)
3
1
4
5
6
2

Explanation:

Step1: Determine valence electrons

Br has 7 valence electrons, each F has 7 valence electrons. Total valence electrons: \(7 + 3\times7=28\)

Step2: Draw Lewis structure

Br is the central atom. Each Br - F bond uses 2 electrons. After bonding 3 F atoms (using \(3\times2 = 6\) electrons), there are \(28- 6=22\) electrons left. Br has 2 lone pairs ( \(2\times2 = 4\) electrons) and 3 bonding pairs.

Step3: Count electron groups

Electron groups = bonding pairs + lone pairs. Bonding pairs = 3, lone pairs = 2. So electron groups \(=3 + 2=5\)

Answer:

5