Chapter U2, Problem 9STP

Interpretation Introduction

Interpretation:

The molecules with double bonds need to be identified.

Concept introduction:

Compounds have chemical and physical properties which help in identifying them. A physical property is a characteristic which can be predicted by physically examining the substance.

Answer to Problem 9STP

(C) O₂, C₂H₄ and H₂CO

Explanation of Solution

Below are the structures of given compounds:

(H₂) (N₂) (O₂) (Cl₂) (C₂H₂) (C₂H₄) (C₂H₆) (H₂CO)

Hydrogen contains one electron in its outermost shell thus, it forms single bond. Nitrogen contains three electrons in its outermost shell thus, it forms triple bond. Oxygen contains two electrons in its outermost shell thus, it forms double bond. Chlorine contains one electron in its outermost shell thus, it forms single bond. The carbon has valency four because it has four electrons in its outermost shell thus it can form 4 bonds with other atoms by sharing of electrons.

Thus, H, Cl can never form double bonds and C when attached to 4 atoms cannot form double bond.

So, the correct option is (C) O₂, C₂H₄ and H₂CO.