Three.
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Two, three or five; three phosphorus chlorides are known: PCl3, P2Cl4, PCl5.
The bond between phosphorus and fluorine atoms is more polar than the bond between phosphorus and chlorine atoms.
PCl5
Two fluorine atoms one chlorine atom and one phosphorus atom make up PClF2.
PCl3
PClF2 is made up of two fluorine atoms one chlorine atom and one phosphorus atom.
In phosphorus trihydride there are four atoms. 1 x phosphorus and 3 x hydrogen. 1 + 3 = 4
One PCl3has one phosphorus (P) and three chlorine (Cl) atoms, so a total of 4 atoms.So, 3PCl3has three phosphorus (P) and nine chlorine (Cl) atoms, so a total of 12 atoms.
The bond between phosphorus and fluorine atoms is more polar than the bond between phosphorus and chlorine atoms.
PCl5
Two fluorine atoms one chlorine atom and one phosphorus atom make up PClF2.
1 P and 5 CI
one
PCl3
PClF2 is made up of two fluorine atoms one chlorine atom and one phosphorus atom.
1
2
There are three single bonds total, one between each of the chlorine atoms and the central phosphorus atom. The phosphorus atom has an additional lone pair of electrons and is thus a has a tetrahedral geometry.