Trigonal Pyramidal. It is not trigonal planar because there is one lone pair around the central atom, just like the shape of ammonia.
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Trigonal Pyramidal
PCl3 is trigonal pyramidal. The lone pair on phosphorous takes up the most space, so the three chlorine atoms form the base of a pyramid with the phosphorous at top.
The reaction will proceed to the right. 2 PCl3 will be consumed.
P+Cl+Cl+Cl 31+35+35+35 so the answer is 136