Question

Identify the number of lone pair and bond pair electrons present in the valence shell of central atom in \(\text{BrF}_3\).

• A. 1 _ Lone pair and 2 _ Bond pair of electrons
• B. 2 _ Lone pair and 2 _ Bond pair of electrons
• C. 2 _ Lone pair and 3 _ Bond pair of electrons
• D. 1 _ Lone pair and 3 _ Bond pair of electrons

Hint:

Count valence electrons of Br and subtract those used for three Br-F bonds.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
In \(\text{BrF}_3\) the central atom is bromine. It has 7 valence electrons (group 17). Three of them pair with fluorine atoms to form three Br-F bonds.

Step 2: Key Formula or Approach:
Bond pairs = number of atoms bonded to the central atom = 3.
Lone pairs = \(\frac{7 - 3}{2} = 2\).

Step 3: Detailed Explanation:
Bromine uses 3 of its 7 electrons for bonding, leaving 4 electrons, which form 2 lone pairs.
So the valence shell has 3 bond pairs and 2 lone pairs, five electron pairs in total. The shape is T-shaped (trigonal bipyramidal arrangement with the two lone pairs in equatorial positions).
Options with only 1 lone pair, or with only 2 bond pairs, do not match three Br-F bonds and seven valence electrons.

Final Answer:
Central bromine carries 2 lone pairs and 3 bond pairs, option (C). \[ \boxed{2\text{ lone pairs and } 3\text{ bond pairs}} \]