Question

what is the molecular geometry of bcl₃? tetrahedral trigonal pyramidal linear trigonal planar

Explanation:

Step1: Determine the Lewis structure of \( BCl_3 \)

Boron (\( B \)) has 3 valence electrons, and each Chlorine (\( Cl \)) has 7 valence electrons. In \( BCl_3 \), Boron forms 3 single bonds with Chlorine atoms. The central \( B \) atom has 3 bonding pairs and 0 lone pairs.

Step2: Apply VSEPR theory

VSEPR (Valence Shell Electron Pair Repulsion) theory states that the molecular geometry is determined by the number of bonding pairs and lone pairs around the central atom. For a central atom with 3 bonding pairs and 0 lone pairs, the electron - pair geometry and molecular geometry is trigonal planar. The bond angles in a trigonal planar geometry are approximately \( 120^{\circ} \). Tetrahedral geometry is for 4 bonding pairs (e.g., \( CH_4 \)), trigonal pyramidal is for 3 bonding pairs and 1 lone pair (e.g., \( NH_3 \)), and linear is for 2 bonding pairs (e.g., \( CO_2 \)).

Answer:

The molecular geometry of \( BCl_3 \) is trigonal planar. So the correct option is the one labeled "trigonal planar".