Question

Which pair of atoms has the highest electronegativity difference?
H – S
H – Cl
N – H
O – H
C – H

Answer 1

Find the electronegativity of the individual atoms and subtract the lowest electronegativity of the 2 from the highest.
For example:
electronegativity of H (hydrogen) is 2.20 and S (sulfur) is 2.58
2.58 - 2.20 = 0.38

Do this for the other 4 too, and you'll know which one has the highest electronegativity difference.