Which pair of atoms has the most polar bond?
(1) h−br
(2) h−cl
(3) i−br
(4) i−cl

option (2) H - Cl

Explanation:

1) The polar character of a covalent bond is defined by the difference in the electronegativities of the atoms. The higher the diffrerence the greater the polar character of the bond.

2) The electronegativities of the elements are found in tables.

These are the electronegativities of the four elements of the question:

H: 2.20 ← lowest

I: 2.66

Br: 2.96

Cl: 3.16 ← highest

3) Since Cl has the greatest electronegativity of the four elements, and H has the lowest one, it is the bond H - Cl which will have the greatest difference of electronegativities, and it is the most polar bond.

your answers are a,b,,e and f

i hope this

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements