PQ 11: VSEPR
The basic fact that determines molecular shapes is that
electron pairs repel each other. Yes. VSEPR theory describes how electron pair repulsion influences molecular geometry.
The electronic geometry of NH3 (ammonia) is
tetrahedral. Yes. NH3 has four RHEDs (Regions of High Electron Density) which means it has a tetrahedral electronic geometry.
The electronic arrangement is the same as the molecular shape when
there are no lone pairs of electrons on the central atom. Yes. The only time that the molecular shape and electronic arrangement are the same is when there are no lone pairs of electrons on the central atom.
When the central atom in a molecule is covalently bonded to five other atoms and has no valence shell nonbonding electrons, then the arrangement of atoms around the central atom is
trigonal bipyramidal. Yes. RHED = 5 and lone pairs = 0, so the electronic and molecular geometries of such a molecular are both trigonal bipyramidal.
The molecular geometry of ammonia (NH3) is
trigonal pyramidal. Yes.NH3 has a tetrahedral electronic geometry. The one lone pair gives NH3 a trigonal pyramidal molecular geometry.