Question

In the structure of \({ClF_3}\), the number of lone pairs of electrons on the central atom \(Cl\) is:

• A. three
• B. one
• C. four
• D. two

Answer 1

The Correct Option is D

To determine the number of lone pairs of electrons on the central atom \(Cl\) in the structure of \(ClF_3\), we need to follow these steps:

1. Identify the total number of valence electrons in \(ClF_3\).
   • Chlorine (Cl) has 7 valence electrons.
   • Each Fluorine (F) atom has 7 valence electrons. Since there are 3 Fluorine atoms, they contribute a total of 3 \times 7 = 21 valence electrons.
   • Therefore, the total number of valence electrons in \(ClF_3\) is 7 + 21 = 28.
2. Determine the electron pair arrangement using VSEPR theory.
   • \(ClF_3\) has 28 valence electrons, which corresponds to 14 electron pairs.
   • Chlorine forms 3 single bonds with Fluorine atoms, using 6 electrons (3 pairs).
   • This leaves 28 - 6 = 22 electrons, or 11 pairs for lone pairs on the Chlorine atom.
   • However, since each bond contains 2 electrons, only the electrons exclusively associated with the Chlorine atom contribute to lone pairs.
3. Calculate the number of lone pairs on the Chlorine:
   • Subtracting the bonded pairs (3 from the 3 single bonds) leaves 2 pairs for the lone pairs.
   • Hence, Chlorine has 2 lone pairs of electrons.
4. Conclusion:
   • The correct answer is that the number of lone pairs of electrons on the central Cl atom in \(ClF_3\) is two.