Question

Which of the following statements is true about hydrogen bonding?

• A. $Cl$ and $N$ have comparable electronegativities yet there is no $H-$bonding in $HCI$ because size of $Cl$ is large
• B. Intermolecular $H-$bonding results in decrease in m.p. and b.p
• C. Ice has maximum density at $0^o$C due to $H-$bonding
• D. $KHC{l}_2\left(HC{l}_2{}^{-}\right)$ exists but $KH{F}_2\left(H{F}_2{}^{-}\right)$ does not exist due to lack of $H-$bonding in $HCl$

Answer 1

The correct option is A $Cl$ and $N$ have comparable electronegativities yet there is no $H-$bonding in $HCI$ because size of $Cl$ is large

There are some limitations to form hydrogen bond for a molecule-

1. Atom must be of $2nd$ period means the size of the atom must be small.

Reason= As we go down in group size of the atom is increase means covalent character also increases.

2. Electronegativity of the atom must be $3$ or more than $3$.

Chlorine:- It follows the $2nd$ condition but the size of $chlorine$ is large that's why some covalent characters also present in the $Chlorine$.

This is the reason $HCl$ has not any hydrogen bonding.

So the correct option is [A].