Chapter 2 Flashcards
A molecular compound containing only carbon and hydrogen atoms
Hydrocarbon
Hydrocarbons having only single (σ) bonds between carbon atoms; the general formula is CnH2n+2
Alkanes
Hydrocarbons having at least one double bond between carbon atoms; the general formula for monocyclic alkenes is CnH2n-2 and the general formula for acyclic alkenes is CnH2n
Alkenes
Hydrocarbons having at least one triple bond between carbon atoms; the general formula for acyclic aklynes is CnH2n-2 and the general formula for monocyclic alkenes is CnH2n+4
Alkynes
A cyclic conjugated unsaturated molecule or ion that is stabilized by π electron delocalization
Aromatic compounds
A compound that doesn’t contain any multiple bonds
Saturated compound
A compound that contains one or more multiple bonds
Unsaturated compound
The prototypical aromatic compound having the formula C6H6
Benzene
A structure in which lines are used to represent bonds
Kekulé structure
A covalent bond in which the electrons are not shared equally because of differing electronegativities of the bonded atoms
Polar covalent bond
A measure of the ability of an atom to attract electrons it is sharing with another and thereby polarize the bond
Electronegativity
A physical property associated with a polar molecule that can be measured experimentally
Dipole moment (µ)
The unit in which dipole moments are stated; 1 D = 1x10^-18 esucm
Debye (D)
The particular group of atoms in a molecule that primarily determines how the molecule reacts
Functional group
Atoms such as oxygen, nitrogen, sulfur, and the halogens that form bonds to carbon and have unshared pairs of electrons
Hereroatom
A molecule with a dipole moment
Polar molecule
The particular group of atoms in a molecule that primarily determines how the molecule reacts
Functional group
The designation given to a fragment of a molecule hypothetically derived from an alkane by removing a hydrogen atom; these group names end in “yl”
Alkyl group
Compounds in which a halogen atom (fluorine, chlorine, bromine, or iodine) replaces a hydrogen atom of an alkane
Alkyl halides or haloalkanes
A carbon that has one other carbon attached to it
Primary carbon atom
A carbon atom that has two other carbon atoms attached to it
Secondary carbon atom
A carbon atom that has three other carbon atoms attached to it
Tertiary carbon atom
An organic halide in which the halogen atom is bonded to an alkene carbon
Alkenyl halides
An organic halide in which the halogen atom is attached to an aromatic ring, such as a benzene ring
Aryl halide
A hydroxyl group attached to a carbon that only has one other carbon attached to it
Primary alcohol
A hydroxyl group attached to a carbon that is attached to two other carbon atoms
Secondary alcohol
A hydroxyl group attached to a carbon that is attached to three other carbon atoms
Tertiary alcohol
When a hydroxyl group is connected to a benzene ring
A phenol group
A group where a carbon atom has a double bond to oxygen
Carbonyl group
Properties of a substance, such as melting point and boiling point, that relate to physical (as opposed to chemical) changes in the substance
Physical property
The temperature at which an equilibrium exists between a well-ordered crystalline substance and the more random liquid state; reflects the energy needed to overcome the attractive forces between the units (ions, molecules) that comprise the crystal lattice
Melting point
Strong electrostatic forces of attraction between ions of opposite charges; these forces hold ions together in a crystal lattice
Ion-ion forces
The temperature at which the vapor pressure of a liquid is equal to the pressure above the surface of the liquid
Boiling point
Forces that act between molecules because of permanent (or temporary) electron distributions; can be attractive or repulsive; includes dipole-dipole forces (including hydrogen bonds) and dispersion forces (also called London forces)
Intermolecular forces (van der Waals forces)
An interaction between molecules having permanent dipole moments
Dipole-dipole force
A strong dipole-dipole interaction that occurs between hydrogen atoms bonded to small strongly electronegative atoms (O, N, or F) and the non bonding electron pairs on other such electronegative atoms
Hydrogen bond
Weak forces that act between non polar molecules or between parts of the same molecule. Bringing two groups (or molecules) together first results in an attractive force between them because a temporary unsymmetrical distribution of electrons in one group induces an opposite polarity in the other. When groups are brought closer than their van der Waals radii, the force between them becomes repulsive because their electron clouds begin to inter penetrate each other
Dispersion force (London force)
The extent to which a given solute dissolves in a given solvent, usually expressed as a weight per unit volume
Solubility
A non polar group that avoids an aqueous surrounding and seeks a non polar environment
Hydrophobic group
A polar group that seeks an aqueous environment
Hydrophilic group
A type of optical spectroscopy that measures the absorption of infrared radiation; provides structural information about functional groups present in the compound being analyzed
Infrared (IR) spectroscopy
A way to express the frequency of a wave; the number of waves per centimeter, expressed as cm^-1
Wave number (v)
The distance between consecutive crests (or troughs) of a wave
Wavelength (λ)
The number of full cycles of a wave that pass a given point in each second
Frequency (v)
