| Dalton's Law of Partial Pressures |
the total pressure of a mixture of gases is the sum of the
partial pressure of the individual gases |
| Decomposition potential |
the minimum voltage necessary to cause electrolysis to take
place |
| Degenerate orbitals |
a group of orbitals with the same energy |
| Dehydrogenation reaction |
a reaction in which two hydrogen atoms are removed from
adjacent carbons of a saturated hydrocarbon, giving an unsaturated hydrocarbon |
| Delocalized electrons |
electrons in a resonance hybrid that are not localized, as
shown by a single Lewis structure |
| Delocalized pi bond |
a pi bond that encompasses more than two atomic nuclei in a
resonance hybrid |
| Denaturation |
the breaking down of the three-dimensional structure of a
protein resulting in the loss of its function |
| Denitrification |
the return of nitrogen from decomposed matter to the
atmosphere by bacteria that change nitrates to nitrogen gas |
| Density |
a property of matter representing the mass per unit volume |
| Deoxyribonucleic acid |
a huge nucleotide polymer having a double helical structure
with complementary bases on the two strands. Its major functions are protein synthesis and
the storage and transport of genetic information |
| Desalination |
the removal of dissolved salts from an aqueous solution |
| Dialysis |
a phenomenon in which a semipermeable membrane allows
transfer of both solvent molecules and small solute molecules and ions |
| Diamagnetism |
a type of magnetism, associated with paired electrons, that
cuases a substance to be repelled from the inducing magnetic field |
| Differential rate law |
an expression that gives the rate of a reaction as a function
of concentrations; often called the rate law |
| Diffraction |
the scattering of light from a regular array of points or
lines, proeducing constructive and destructive interference |
| Diffusion |
the mixing of gases |
| Dimer |
a molecule formed by joining the two identical monomers |
| Dipole-dipole moment |
a relatively weak attraction between molecules that are
permanent dipoles |
| Direct reduction furnace |
a furnace in which iron oxide is reduced to ion metal using
milder reaction conditions than in a blast furnace |
| Disaccharide |
a sugar formed from two monosaccharides joined by a glycoside
linkage |
| Disproportionation reaction |
an oxidation -reduction reaction in which one element is both
oxidized and reduced |
| Dissociation constance |
the equilibrium constant for the ionization reactoin of a
weak acid or a weak base |
| Distillation |
the process of vaporizing a liquid followed by condensation
of the vapor as a method of purifying the liquid |
| Disulfide linking |
an S-S bond that stabilizes the tertiary structure of many
proteins |
| Double bond |
a covalent bond composed of two pairs of shared electrons |
| Downs cell |
a cell used for electrolyzing molten sodium chloride |
| Dry cell battery |
a voltaic cell containing no liquid phases |
| Dual nature of light |
the statement that light exhibits both wave and particle
properties |
| Ductile |
capable of being drawn into a thin shape such as a wire |
