Answer
General guidance
The bond formed from the elements has a higher electronegativity difference which tends to have ionic bonding.
Example: 
In hydrogen fluoride, hydrogen is less electronegative and fluorine is more electronegative. The more electronegativity difference leads to ionic bonding.
The bonds formed from the elements have more or less electronegativity difference that tends to have covalent bonding.
Example: 
In methane, carbon contains 4 valance electrons and 4 hydrogen contain 1 electron each. Therefore, both carbon and hydrogen shares its electron and form covalent bond. The electronegativity difference between carbon and 4 hydrogen’s is less.
Step-by-step
Step 1 of 3
(A)
In the molecule
, both atoms belong to the halogen family. On moving from top to bottom in the periodic table, electronegativity decreases. As fluorine is more electronegative than iodine, iodine will not be in the negative pole.
In the molecule, the fluorine atom has the negative pole. This is due to a higher electronegativity of fluorine than iodine.
In the molecule
, the atom that has the negative pole is given below:
Electronegativity decreases on moving down the group. The electronegativity of fluorine is more than iodine. Therefore, in molecule, fluorine atom has the negative pole.
Step 2 of 3
(B)
Electronegativity decreases on moving down the group. Electronegativity of chlorine is less than fluorine. Therefore, the bonds in 
are not more polar.
In halogen family, fluorine is more electronegative than chlorine, bromine and iodine. The atom with a greater electronegativity difference makes the molecule to be more polar. Therefore, the bonds in 
molecule are more polar.
The more polar bonds in the molecule is given below:
In molecule, there are three fluorine atoms that bonded to a central phosphorus atom. In periodic table, fluorine is more electronegative than other elements. More electronegative atom is more polar. Therefore, the bonds in molecule are more polar.
Step 3 of 3
(C)
The arrow cannot move to the right, because all three atoms attached to phosphorus are same. Therefore, all three atoms have the same behavior.
The arrow cannot move to the left, because all three atoms attached to phosphorus are same. Therefore, all three atoms have the same behavior.
The polarity arrow moves to more electronegative atom. Phosphorus is less electronegative than fluorine. Therefore, the arrow cannot move towards the central phosphorus atom.
The polarity arrow moves away from central phosphorus atom, as fluorine is more electronegative than phosphorus.
The polarity arrow point:
|
O |
To the right |
|
O |
To the left |
|
O |
Toward the central phosphorus atom |
|
O |
Away from the central phosphorus atom |
The polarity arrow always moves towards the most electronegative atom. In the molecule, there are three fluorine atom bonded to phosphorus atom, in which fluorine is more electronegative than phosphorus. Therefore, the polarity arrow moves towards the fluorine atom.
Answer
In the molecule, the atom that has the negative pole is given below:
The more polar bonds in the molecule is given below:
The polarity arrow point:
|
O |
To the right |
|
O |
To the left |
|
O |
Toward the central phosphorus atom |
|
O |
Away from the central phosphorus atom |
Answer only
In the molecule, the atom that has the negative pole is given below:
The more polar bonds in the molecule is given below:
The polarity arrow point:
|
O |
To the right |
|
O |
To the left |
|
O |
Toward the central phosphorus atom |
|
O |
Away from the central phosphorus atom |
