Chapter 2.2, Problem 4QQ

Interpretation Introduction

Interpretation:

The statement concerning alkene ${\text{CH}}_{\text{2}}=\text{CH}-{\text{CH}}_{\text{3}}$ is correct among the given statements has to be identified.

Concept Introduction:

Hydrocarbons are the organic compounds that contain only hydrogen and carbon atoms.  Hydrocarbon derivatives are the one in which the compounds contain hydrogen and carbon atoms along with one or more additional elements.  The additional elements that can be present in hydrocarbon derivatives are oxygen, nitrogen, sulphur, chlorine, bromine etc.

Hydrocarbons are further classified into two categories.  They are saturated hydrocarbons and unsaturated hydrocarbons.  The hydrocarbons that contain single bonds between carbon atoms in the entire molecule is known as saturated hydrocarbon.  The hydrocarbons that contain atleast one double or triple bond between two carbon atoms in the entire molecule is known as unsaturated hydrocarbon.

Saturated hydrocarbons are alkanes.  Unsaturated hydrocarbons are alkene, alkyne and aromatic hydrocarbons.

Alkane has general molecular formula as ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n+2}}$.  Alkene in which one double is present has general molecular formula as ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n}}$.  Alkyne in which one triple bond is present has the general molecular formula as ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n-2}}$.  Cycloalkanes have the general molecular formula as ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n}}$.  Cycloalkenes in which one double bond is present have the general molecular formula as ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n-2}}$.

Considering the geometry of carbon atoms, the carbon atoms that have double bonds will have trigonal planar geometry.  The carbon atoms that have only single bonds attached to it will have tetrahedral geometry.  The carbon atoms that have a triple bond attached to it will have a linear geometry.