Question

A molecule with the formula ab3 has a trigonal planar geometry. part a how many electron groups are on the central atom?

Answer 1

A molecule with the formula AB3 has a trigonal planar geometry and the central atom has three electron groups around it.

Step-by-step explanation:

The molecule with the formula AB3 has a trigonal planar geometry. In trigonal planar geometry, the central atom has three electron groups around it. This includes the three bonds in the molecule. The three electron groups repel each other to adopt positions of an equilateral triangle, 120° apart and in a plane.

Answer 2

Answer: 3 electron pairs Let's take BF3 for an example. When you find the valence electrons for this molecule --> [3+(3x6)], you'll get 24e-. You draw the Lewis dot structure and each of the F atom would have six dots around it (a total of 18 because there's 3 F atoms) and the B would have three lines [one line attached to each F. One line would equal to 2 valence electrons] and you get a total of 24 valence e-. The question asks how many groups are on the CENTRAL atom, meaning on the B. It would be three