Properties of Organic Chemistry

• Carbon has four valence electrons that can form covalent bonds with other atoms.
• Alkanes have single bonds between carbon atoms and no double or triple bonds.
• Organic compounds are made up of carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus, silicon, or halogens.
• Covalent compounds are formed when two or more nonmetal elements share pairs of electrons to complete their outer shells.
• Alkanes are saturated hydrocarbons that contain only single covalent bonds between carbon atoms.
• Polar covalent bonds allow polar molecules to form permanent dipoles.
• The differences in electronegativity create polar covalent bonds, making one end slightly positive and one end slightly negative.
• Carbon atoms can form multiple bonds to other carbon atoms or nonmetals through double and triple covalent bonds.
• Polar covalent bonds form when there is an unequal sharing of electrons between atoms, creating partial positive and negative ends.
• The C-H bond is polarized, with the carbon atom being slightly positive.
• The general formula for alkanes is CnH2n+2, where n represents the number of carbons in the molecule.
• Alkenes have the general formula CnH2n.
• Alkenes are hydrocarbons containing at least one carbon-to-carbon double bond (C=C).
• The general formula for alkanes is CnH2n+2.
• Alkanes have the same number of carbons as hydrogens.
• Alkanes are saturated because they contain only single bonds.
• Alkenes are unsaturated hydrocarbons containing at least one carbon-to-carbon double bond (C=C).
• The general formula for alkenes is CnH2n.
• The boiling point of an organic compound is determined by the strength of intermolecular forces.
• Intermolecular forces include London dispersion forces (weakest), dipole-dipole interactions, and hydrogen bonding (strongest).
• Nonpolar covalent bonds occur when the difference in electronegativities is small, resulting in equal sharing of electron density by both atoms.
• Alkenes have at least one carbon-carbon double bond (C=C) and are unsaturated hydrocarbons.
• Solubility Test as you have learned in your previous chemistry classes. Solubility of any compounds are determined by these factors:
• Electrical Conductivity: The easiest way to determine whether a compound can conduct a current is to identify its molecular structure or composition. Compounds with strong conductivity dissociate completely into charged atoms or molecules, or ions, when dissolved in water. These ions can move and carry a current effectively. The higher the concentration of ions, the greater the conductivity.
• Qualitative Analysis of Organic Compounds The most commonly occurring elements in organic compounds are carbon, hydrogen, oxygen, nitrogen, sulphur and halogen elements. There is no direct method for the detection of oxygen. For detecting nitrogen, sulphur and halogens, we can use the sodium fusion test (Lassaigne’s test).
• Sodium Fusion Test This test is used for the qualitative analysis of elements nitrogen, sulphur and halogen in Organic compounds. In order to detect them, it is necessary to convert them into ionizable inorganic substances.
• A Prussian blue precipitate or colouration indicates that nitrogen is present.
• The hexacyanoferrate (II) reacts with the iron (III) salt, producing iron (III) hexacyanoferrate (II), Prussian blue.
• Test for Carbon and Hydrogen Carbon and hydrogen are detected by heating the compound with copper(II)oxide.
• Carbon present in the compound is oxidized to carbon dioxide and hydrogen to water.
• Test for Sulfur The sodium fusion extract is acidified with acetic acid and lead acetate is added to it. A black precipitate of lead sulphide indicates presence of sulphur.
• Separations Based on Size Size is the simplest physical property we can exploit in a separation. To accomplish the separation we use a porous medium through which only the analyte or the interferent can pass. Examples of size-based separations include filtration, dialysis, and size-exclusion.
• Separations based on mass or density can be achieved through centrifugation if the analyte and the interferent have different masses or densities
• In centrifugation, the sample is placed in a centrifuge tube and spun at a high angular velocity, measured in revolutions per minute (rpm)
• The sample's constituents experience a centrifugal force that pulls them toward the bottom of the centrifuge tube
• Species that experience the greatest centrifugal force have the fastest sedimentation rate and are the first to reach the bottom of the centrifuge tube
• If two species have the same density, their separation is based on a difference in mass, with the heavier species having the greater sedimentation rate
• If species are of equal mass, then the species with the larger density has the greatest sedimentation rate
• Separations Based on Complexation Reactions (Masking) One widely used technique for preventing an interference is to bind the interferent in a strong, soluble complex that prevents it from interfering in the analyte’s determination. This process is known as masking. A wide variety of ions and molecules are useful masking agents, and, as a result, selectivity is usually not a problem
• Technically, masking is not a separation technique because we do not physically separate the analyte and the interferent. We do, however, chemically isolate the interferent from the analyte, resulting in a pseudo-separation.