14. the molecule that has a molecular shape of trigonal pyramidal is _ i because _ ii\nthe statement above…

14. the molecule that has a molecular shape of trigonal pyramidal is _ i because _ ii\nthe statement above is best completed by the answers in row:\nrow i ii\n□ ph₃ the central atom has a lone pair\n□ bh₃ the central atom has a lone pair\n□ ph₃ the central atom has no lone pairs\n□ bh₃ the central atom has no lone pairs

14. the molecule that has a molecular shape of trigonal pyramidal is _ i because _ ii\nthe statement above is best completed by the answers in row:\nrow i ii\n□ ph₃ the central atom has a lone pair\n□ bh₃ the central atom has a lone pair\n□ ph₃ the central atom has no lone pairs\n□ bh₃ the central atom has no lone pairs

Answer

Explanation:

Step1: Recall molecular - geometry rules

The molecular geometry of a molecule depends on the number of bonding pairs and lone - pairs around the central atom. For a trigonal - pyramidal shape, the central atom has 3 bonding pairs and 1 lone pair.

Step2: Analyze (PH_3) and (BH_3)

  • In (PH_3), the central phosphorus ((P)) atom has 5 valence electrons. It forms 3 single bonds with hydrogen ((H)) atoms, using 3 of its valence electrons. So, there is 1 lone pair of electrons on the (P) atom ((5 - 3=2) non - bonding electrons or 1 lone pair). The electron - pair geometry around (P) is tetrahedral ((3) bonding pairs and (1) lone pair), and the molecular geometry is trigonal pyramidal.
  • In (BH_3), the central boron ((B)) atom has 3 valence electrons. It forms 3 single bonds with hydrogen ((H)) atoms, using all of its valence electrons. There are no lone pairs on the (B) atom. The electron - pair geometry and molecular geometry of (BH_3) are trigonal planar.

Answer:

PH₃; the central atom has a lone pair