9. What is the molecular geometry of PH_(3) __

The molecular geometry of (phosphine) is trigonal pyramidal. Here's the reasoning:1. **Valence Electrons**: Phosphorus (P) has 5 valence electrons, and each hydrogen (H) atom contributes 1 valence electron. Therefore, the total number of valence electrons in is .2. **Lewis Structure**: In the Lewis structure of , phosphorus is the central atom bonded to three hydrogen atoms. This uses up 6 of the 8 valence electrons (2 electrons per bond), leaving 2 electrons as a lone pair on the phosphorus atom.3. **Electron Pair Geometry**: The electron pair geometry around phosphorus is tetrahedral because there are four regions of electron density (three P-H bonds and one lone pair).4. **Molecular Geometry**: The presence of the lone pair affects the molecular shape. The lone pair-bond pair repulsion is greater than bond pair-bond pair repulsion, which pushes the hydrogen atoms closer together, resulting in a trigonal pyramidal shape.Therefore, the molecular geometry of is trigonal pyramidal.