Which compound has trigonal planar geometry?
A. CHCl3
B. NH3
C. BCl3
D. HCN
D?
No. D is linear planar. For many of your questions you may want to try Google. For example, I thought HCN was a linear molecule so I Googled "is HCN a linear molecule". The answer was it is a linear molecule. Try that with BCl3
To determine the compound that has trigonal planar geometry, we need to examine the Lewis structure of each compound and identify the arrangement of atoms around the central atom.
Let's go through each compound:
A. CHCl3 (chloroform) - The central atom is carbon (C), bonded to three hydrogen (H) atoms and one chlorine (Cl) atom. The Lewis structure of CHCl3 shows that the carbon atom has four regions of electron density, making the molecular geometry tetrahedral, not trigonal planar.
B. NH3 (ammonia) - The central atom is nitrogen (N), bonded to three hydrogen (H) atoms. The Lewis structure of NH3 reveals that the nitrogen atom has three regions of electron density, resulting in a trigonal pyramidal molecular geometry, not trigonal planar.
C. BCl3 (boron trichloride) - The central atom is boron (B), bonded to three chlorine (Cl) atoms. The Lewis structure of BCl3 shows that the boron atom has three regions of electron density, leading to a trigonal planar molecular geometry.
D. HCN (hydrogen cyanide) - The central atom is carbon (C), bonded to a hydrogen (H) atom and a nitrogen (N) atom. The Lewis structure of HCN demonstrates that the carbon atom has two regions of electron density, while the nitrogen atom has three regions of electron density, yielding a linear molecular geometry.
Therefore, the only compound with trigonal planar geometry is C. BCl3 (boron trichloride).
Note: It's essential to understand the concept of electron density and how to determine molecular geometry to solve such questions.