Question

Which of the following has strongest hydrogen bonds in the following linkages is:
(i) $O-H---S$
(ii) $S-H---O$
(iii) $F-H---F$
(iv) $F-H---O$
where, $-$ represents covalent bond and $---$ represents hydrogen bond.

• A. (iii)
• B. (ii)
• C. (i)
• D. (iv)

Answer 1

The correct option is A (iii)

The Strength of $H-$ bonding depends upon the following factors.
(i) Electronegativity of the element covalently bonded to the hydrogen atom.
(ii) Size of the electronegative element.
(iii) Ease of donation of lone pair of electrons by the electronegative element.

As Fluorine (F) is the most electronegative atom followed by Oxygen(O) and then Sulfur(S), Therefore in option (a) the strength of hydrogen bonding in $F-H---F$ is strongest.