Answer:
It has one bond with each chlorine in order to attain the octet forming a pyramid-like structure.
Step-by-step explanation:
Hello,
In this case, for building a ball-and-stick model of phosphorous trichloride (PCl3) it is necessary to know that since phosphorous has five valance electrons, it need three electrons to attain the octet, that is why three bonds with chlorine are formed in a pyramid-like structure since each chlorine is able to share those electrons. You can verify that on the attached picture.
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