HYDROCARBONS
Pharm 122L - Preliminary Term
Prepared by: Mary Grace S. Biagtan, RP h, MS P harm
OVERVIEW
01
INTRODUCTION TO HYDROCARBONS
02
PART 1: ALKANES
03
PART 2: ALKENES
04
PART 3: ALKYNES
HYDROCARBONS
• contain only H and C
• Saturated: all C to C bonds are single
• Unsaturated: contain C to C multiple
bonds
• Alkanes (C-C)
• Alkenes (C=)
• Alkynes (C≡C)
HYDROCARBONS
ALKANES ALKENES ALKYNES
each carbon atom HC with one or HC with one or
has four single more carbon–carbon more carbon-
double bonds carbon triple bonds
bonds
Chemical Reactions
characteristics of a substance that describe the way the substance
undergoes or resists change to form a new substance
Physical Properties Applications
can be measured and examples of products and
observed without their pharmaceutical and
changing the composition industrial uses
or identity of a substance
PHYSICAL PROPERTIES OF
ALKANES & CYCLOALKANES
• Insoluble in water
• Density: 0.6 g/mL to 0.8 g/mL
• Boiling Point: increases as the C-
chain length increases
• Cycloalkanes have higher BP than
non-cyclic counter parts
PHYSICAL PROPERTIES
OF ALKANES
• State
• Gas: 1-4 C atoms
• Liquid: 5-17 C atoms
• Solid: 18 or more
#1: The density difference between
alkanes & cycloalkanes and water
Fun Fact
explains why oil spills in aqueous
environments spread so quickly.
#2: Samgyupsal grill pan stove
makes use of portable butane gas
(hydrocarbon with 4C atoms).
CHEMICAL REACTIONS OF
ALKANES & CYCLOALKANES
• Combustion
• Halogenation
• Oxidation
• Type
• Reactants
• Catalysts
• Products
I. Combustion
• alkane + oxygen that proceeds with the
evolution of heat and light
• products: carbon dioxide + water
Combustion of Methane and Propane
CH4 + O2 → 2CO2 + 2H2O + heat energy
C3H8 + 5O2 → 3CO2 + 4H2O + heat energy
Application
“the exothermic nature of alkane combustion
reactions explains the extensive use of alkanes as
fuels”
Natural Gas Gasoline as
Propane in
in Home Transportation
Barbecue Units
Heating Fuel
2. Incomplete Combustion
• occur if insufficient oxygen is present during the
process
• products: CO2, carbon monoxide and elemental
carbon
Incomplete Combustion of Propane
C3H8 + 2O2 → 3C + 4H2O
Fun Fact
The appearance of deposits of
black carbon (soot) on the
bottom of the pot is a physical
evidence that incomplete
combustion is occurring.
3. Halogenation
• alkane + halogen in which one or more
halogen atoms are incorporated into
molecules of the alkane
• Fluorination, chlorination, bromination, or
iodination
Bromination of Cyclohexane
Reaction with Bromine Water
“UV light splits the bromine molecule into two
reactive radicals, resulting in a very slow loss of
amber bromine color.”
Bromination of Ethane
4. Oxidation
• loss of electrons or gain of oxygen, resulting
in an increase in oxidation state by a
molecule, atom or ion
“Alkanes are relatively
inert to chemical oxidizing
agents such as potassium
Potassium
Permanganate
Solution
permanganate.”
Alkane-Containing
Products
• Halothane
• Hexane
• Sodium Lauryl Sulfate
• Uses
• Other Names
• Structure
Halothane
• AKA: Fluorothane
• MF: C2HBrClF3
• IUPAC Name: 2-bromo-2-chloro-1,1,1-trifluoroethane
• Use: General Anesthetic
• ROA: Inhalation
Hexane
• Molecular Formula: C6H14
• Properties:
• clear colorless liquids with a petroleum-like odor
• less dense than water and insoluble in water
• flammable and explosive
• Uses: solvent, paint thinner, and chemical reaction medium
Sodium Lauryl Sulfate
• AKA Sodium monododecyl sulfate
• MF: C12H25O4SNa
• combined content of sodium chloride and sodium sulfate is not
more than 8%
• Uses: An emulsifying agent/detergent, and wetting agent in
ointments, tooth powders, and other pharmaceutical preparations,
and in the metal, paper, and pigment industries.
HYDROCARBONS
Thank you very much for your
time and attention!
