Pick the correct pair of species that can form hydrogen bond with water. (a) ch, hcooh (b) f, hcooh (c) f .ch, och, (d) both (b) and (c)

(B) F⁻, HCOOH

Explanation:

(A) CH₄, HCOOH

(B) F⁻, HCOOH

(C) F⁻, CH₃-O-CH₃

The hydrogen bonds are formed when the hydrogen is found between two electronegative atoms such as oxygen (O), nitrogen (N) or florine (F).

O····H-O, F····H-O, O····H-N

(A) CH₄, HCOOH

- here methane CH₄ is not capable to form hydrogen bond with water

- formic acid HCOOH can form hydrogen bonds with water

H-C(=O)-O-H····OH₂

(B) F⁻, HCOOH

-both floride (F⁻) and formic acid can form hydrogen bonds with water

F····OH₂

H-C(=O)-O-H····OH₂

(C) F⁻, CH₃-O-CH₃

-  dimethyl-ether CH₃-O-CH₃ is not capable to form hydrogen bond with water

- floride (F⁻) can form hydrogen bonds with water

F····OH₂

58 km per hour : d

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