Of electrons; refers to bonding electrons that are distributed among more than two atoms that are bonded together; occurs in species that exhibit resonance.
The formation of a set of molecular orbitals that extend over more than two atoms; important in species that valence bond theory describes in terms of resonance.
A process pertaining to a change in structure of a protein form regular to irregular arrangement of the polypeptide chains.
A commercial term used to describe ethanol that has been rendered unfit for human consumption because of the addition of harmful ingredients to make it sales tax-expempt.
Mass per unit Volume: D=MV
The direct solidification of a vapor by cooling; the reverse of sublimation.
A compound that can be imagined to arise from a partent compound by replacement of one atom with another atom or group of atoms. Used extensively in orgainic chemistry to assist in identifying compounds.
Adverse health effects resulting from skin exposure ot a substance.
An area that may be used for work with carcinogens, reproductive toxins, or substances that have a high degree of acute toxicity. A designated area may be the entire laboratory, an area of a laboratory, or a device such as a loboratory hood.
A soap-like emulsifer that contains a sulfate, SO3 or a phosphate group instead of a carboxylate group.
An isotope of hydrogen whose atoms are twice as massive as ordinary hydrogen;deuterion atoms contain both a proton and a neutron in the nucleus.
Refers to an optically active substance that rotates the plane of plane polarized light clockwise; also called dextro.
Refers to chemical similarities in the Periodic Table of elements of Period 2 to elements of Period 3 one group to the right; especially evident toward the left of the periodic table.
Weak repulsion by a magnetic field.
Differential Scanning Calorimetry (DSC)
A technique for measuring the temperature, direction, and magnitude of thermal transitions in a sample material by heating/cooling and comparing the amount of energy required to maintain its rate of temperature increase or decrease with an inert reference material under similar conditions.
Differential Thermal Analysis (DTA)
A technique for observing the temperature, direction, and magnitude of thermally induced transitions in a material by heating/cooling a sample and comparing its temperature with that of an inert reference material under similar conditions.
A thermometer used for accurate measurement of very small changes in temperature.
Process of reducing the concentration of a solute in solution, usually simply by mixing with more solvent.
Molecule formed by combination of two smaller (identical) molecules.
Refers to the separation of charge between two covalently bonded atoms
Attractive interactions between polar molecules, that is, between molecules with permanent dipoles.
The product of the distance separating opposite charges of equal magnitude of the charge; a measure of the polarity of a bond or molecule; a measured dipole moment refers to the dipole moment of an entire molecule.