Question

If a solid line represents a covalent bond and a dotted line represents intermolecular attraction, which of the choices shows a hydrogen bond? H−H H4C⋅⋅⋅⋅⋅⋅H−F H3N⋅⋅⋅⋅⋅⋅H−O−H H2O⋅⋅⋅⋅⋅⋅H−CH3

Answer 1

Answer:

H₃N------H - O - H

and

H₄C ------ H - F

shows Hydrogen bonding.

Explanation:

Hydrogen bonding -

The interaction between hydrogen atom , with an electronegative atom like, N , F, O etc. ,tends to stabilizes the compound, this type of interaction is called Hydrogen bonding .

From the given structure ,

H₃N------H - O - H

Hydrogen bonding is possible in this compound as,

the highly electronegative N is linked to H .

H₂O ------ H-CH₃

Hydrogen bonding is possible in this compound as,

the highly electronegative O is linked to H .

H₄C ------ H - F

No hydrogen bonding ,

as Carbon electronegativity is not high.

So, can not show hydrogen bonding .

Therefore,

only H₃N------H - O - H and H₂O ------ H-CH₃ shows Hydrogen bonding .

Answer 2

Answer: $H_{3}N-H-O-H$ shows a hydrogen bond is the correct answer.

Explanation:

A hydrogen bond is defined as a weak bond that is formed between an electropositive atom (generally hydrogen atom) and an electronegative atom like oxygen, nitrogen and fluorine.

This bond is formed due to difference in the electronegativity of atoms present in a compound which contains a hydrogen bond. So, there occurs a partial positive charge on hydrogen atom and a partial negative charge on the electronegative atom.

For example, $H_{3}N-H-O-H$ molecule will have hydrogen bonds.

This is because both nitrogen and oxygen atoms are electronegative in nature. Therefore, partial charges will develop on the both electronegative and electropositive atoms of this compound.

Thus, we can conclude that out of the given options $H_{3}N-H-O-H$ shows a hydrogen bond.