You would expect a phosphorous-chlorine bond to be
1. nonpolar, with the neither end having a
partial charge.
2. polar, with neither end having a partial
charge.
3. nonpolar, with the chlorine end having a
partial negative charge.
4. polar, with the chlorine end having a
partial negative charge.
5. nonpolar, with the phosphorus end having
a partial negative charge.
6. polar, with the phosphorus end having a
partial negative charge.
explain why

option 4. polar, with the chlorine end having a partial negative charge.

Explanation:

1) A polar bond is a covalent bond in which the electrons are pulled more strongly by one of the atoms and then they are not evely distributed between the two linked atoms.

2) That happens when the two atoms have diferent electronegativities.

3) As the per periodic table trend of the electronegativity, you can predict that the electronetativity of Cl is higher than that of P.

In fact, in a table of electronegativities you can find that the electronegativity of Cl is 3.16 while the electronegativity of P is 2.19.

This is a 3.16 - 2.19 = 0.97 difference.

As explained, that difference means that Cl will pull the electrons more strongly resulting if a partial negative charge on Cl and a partial positive charge on P, i.e. a polar bond.

let that person have a turn to speak : )