Table of Contents
What are Alkenes?
Alkenes are a type of hydrocarbon that contain at least one carbon-carbon double bond. This double bond is what differentiates alkenes from alkanes, which only contain single bonds. Alkenes are important because they are used to make plastics, synthetic rubber, and other types of chemicals. Physical Properties of Alkenes – Polarity Boiling Point Density
Structural Isomerism
Structural isomerism is a type of isomerism in which molecules with the same chemical formula but different structural formulae are isomers. In structural isomerism, the atoms in the molecules are connected by different covalent bonds.
Geometric Isomerism
In organic chemistry, geometric isomerism (or configurational isomerism) is a form of stereoisomerism in which molecules with the same molecular formula have different shapes because of the way their atoms are arranged around their chiral centers.
Properties of Alkenes
Alkenes are hydrocarbons that contain one or more carbon-carbon double bonds. Alkenes are less dense than hydrocarbons with single bonds and are more soluble in nonpolar solvents. They are also more flammable and reactive than hydrocarbons with single bonds.
Physical State of Alkenes
Alkenes are typically in the liquid state at room temperature.
Polarity
Positive
Negative
Polarity is the charge of an atom or molecule. The polarity of an atom is determined by the number of protons in the nucleus. The polarity of a molecule is determined by the number of polar bonds it has.
Density and Solubility
The density of a substance is its mass per unit volume. The higher the density, the more mass per unit volume. The solubility of a substance is the maximum amount of the substance that will dissolve in a given amount of solvent at a given temperature.
Boiling Point
The boiling point is the temperature at which the vapor pressure of a liquid is equal to the atmospheric pressure.
Boiling Points of Alkenes
The boiling points of alkenes increase as the number of carbon atoms in the molecule increases.
The boiling points of alkenes also increase as the number of hydrogen atoms in the molecule decreases.
Melting Point
The melting point of a substance is the temperature at which the solid and liquid phases are in equilibrium.
Melting Points of Alkenes
The melting points of alkenes increase as the number of carbon atoms in the molecule increases. The following table lists the melting points of some common alkenes.
Alkenes Melting Points
ethylene (C2H4) -127.0°C
propylene (C3H6) -188.0°C
butene (C4H8) -104.0°C
pentene (C5H10) -68.0°C
hexene (C6H12) -49.0°C
heptene (C7H14) -36.0°C
octene (C8H16) -30.0°C
Physical Properties of Alkenes – Polarity Boiling Point Density.
