No, PH3 is not symmetric. The molecule has a pyramidal shape due to the lone pair on the central phosphorus atom. This asymmetry contributes to the overall molecular geometry of PH3.
Phosphine (PH3) forms a molecular solid in which individual PH3 molecules are held together by weak van der Waals forces.
Trigonal Pyramidal
Phosphine, or PH3, has (quite obviously) three hydrogen atoms singly bonded to a phosphorus atom. Because of the presence of a lone pair of electrons, the phosphorus atom is sp3 hybridized, and the electron orbitals adopt a tetrahedral configuration. As mentioned earlier, one orbital is non-bonding and thus the molecular shape is trigonal pyramidal.
PH3 is a molecular compound. It is made up of covalent bonds between phosphorus and hydrogen atoms, rather than ionic bonds between a metal and a nonmetal.
PH3: Trigonal pyramidal CH4: Tetrahedral HClO: Bent N2: Linear CH3NH2: Trigonal pyramidal H2CO: Trigonal planar C2H2: Linear CH3Cl: Tetrahedral HCOOH: Bent HCN: Linear H2O2: Bent
PCL5: Trigonal bipyramidal shape PH3: Trigonal pyramidal shape OF2: Bent shape ClO4-: Tetrahedral shape
The bond angle in PH4 is higher than PH3 because PH4 has a tetrahedral molecular geometry with bond angles of about 109.5 degrees, while PH3 has a trigonal pyramidal molecular geometry with bond angles of about 107 degrees. This difference in bond angles is due to the presence of an additional hydrogen atom in PH4 compared to PH3.
A PH3 molecule has a triangular pyramidal shape. The central atom is the Phosphorus atom, which is connected to three Hydrogen atoms.
BeCl2
The parent structure of PH3 is trigonal pyramidal. It consists of a central phosphorus atom with three hydrogen atoms bonded to it, giving it a pyramidal shape.
PH3 has a higher vapor pressure than NH3 due to the larger size and greater molecular weight of phosphorus compared to nitrogen. This results in weaker van der Waals forces between PH3 molecules, allowing them to escape and become a gas more easily than NH3 molecules.