- Salt Bridge
- A U-shaped tube containing electrolyte, which connects two half-cells of a
- Hydrolysis of esters in the presence of strong soluable bases.
- Saturated Hydrocarbons
- Hydrocarbons that contain only single bonds. They are also called alkanes
or paraffin hydrocarbons.
- Saturated Solution
- Solution in which no more solute will dissolve.
- Second Law of Thermodynamics
- The universe tends toward a state of greater diorder in spontaneous
- Secondary Standard
- a solution that has been titrated against a primary standard. A standard
solution is a secondary standard.
- Secondary Voltaic Cells
- Voltaic cells that can be recharged; original reactanats can be
regenerated be reversing the direction of the current flow.
- A substance that does not conduct electricity at low temperatures but does
so at higher temperatures.
- Semipermable Membrane
- A thin partition between two solutions through which certain molecules can
pass but others cannot.
- Shielding Effect
- Electrons in filled sets of s , p orbitals between the nucleus and outer
shell electrons shield the outer shell electrons somewhat from the effect of
protons in the nucleus; also called screening effect.
- Sigma Bonds
- Bonds resulting from the head-on overlap of atomic orbitals, in which the
region of electron sharing is along and (cylindrically) symmetrical to the
imaginary line connecting the bonded atoms.
- Sigma Orbital
- Molecular orbital resulting from head-on overlap of two atomic orbitals.
- Polymeric organosilicon compounds; contain individual or cross-linked Si-O
chains or rings in which some oxygens of SiO4 tetrahedra are replaced by other
- Single Bond
- Covalent bond resulting from the sharing of two electrons (one pair)
between two atoms.
- Solubility Product Constant
- Equilibrium constant that applies to the dissolution of a slightly soluble
- Solubility Product Principle
- The solubility product constant expression for a slightly soluble compound
is the product of the concentrations of the constituent ions, each raised to the
power that corresponds to the number of ions in one formula unit.
- The dispersed (dissolved) phase of a solution.
- Homogeneous mixture of two or more substances.
- The process by which solvent molecules surround and interact with solute
ions or molecules.
- The dispersing medium of a solution.
- The reaction of a substance with the solvent in which it is dissolved.
- S Orbital
- A spherically symmetrical atomic orbital; one per energy level.
- Specific Gravity
- The ratio of the density of a substance to the density of water.
- Specific Heat
- The amount of heat required to raise the temperature of one gram of
substance one degree Celsius.
- Specific Rate Constant
- An experimentally determined (proportionality) constant, which is different
for different reactions and which changes only with temperature; k in the
rate-law expression: Rate = k [A] x [B]v.
- Spectator Ions
- Ions in a solution that do not participate in a chemical reaction.
- Spectral Line
- Any of a number of lines corresponding to definite wavelengths of an atomic
emission or absorption spectrum; represents the energy difference between two
- Spectrochemical Series
- Arrangement of ligands in order of increasing ligand field strength.
- Display of component wavelengths (colours) of electromagnetic radiation.
- Square Planar
- A term used to describe molecules and polyatomic ions that have one atom in
the center and four atoms at the corners of a square.
- Square Planar Complex
- Complex in which the metal is in the center of a square plane, with ligand
donor atoms at each of the four corners
- Standard Electrodes
- Half-cells in which the oxidized and reduced forms of a species are present
at unit activity; 1.0M solutions of dissolved ions, 1.0atm partial pressure of
gases, and pure solids and liquids.
- Standard Electrode Potential
- By convention , potential, Eo, of a half-reaction as a reduction relative
to the standard hydrogen electrode when all species are present at unit
- Standard Entropy
- The absolute entropy of a substance in its standard state at 298 K.
- Standard Molar Enthalphy of Formation
- The amount of heat absorbed in the formation of one mole of a substance in
a specified state from its elements in their standard states.
- Standard Molar Volume
- The volume occupied by one mole of an ideal gas under standard conditions;
- Standard Reaction
- A reaction in which the numbers of moles of reactants shown in the balanced
equation, all in their standard states, are completely converted to the numbers
of moles of products shown in the balanced equation, also sall at their standard
- Isomers that differ only in the way that atoms are oriented in space;
consist of geometrical and optical isomers.
- Description of the quantitative relationships among elements and compounds
as they undergo chemical changes.
- Strong Electrolyte
- A substance that conducts electricity well in a dilute aqueous solution.
- Strong Field Ligand
- Ligand that exerts a strong crystal or ligand electrical field and
generally forms low spin complexes with metal ions when possible.
- Structural Isomers
- Compounds that contain the same number of the same kinds of atoms in
different geometric arrangements.
- The direct vaporization of a sold by heating without passing through the
- Any kind of matter all specimens of which have the same chemical
composition and physical properties.
- Substitution Reaction
- A reaction in which an atom or a group of atoms is replaced by another atom
or group of atoms.
- Supercooled Liquids
- Liquids that, when cooled, apparently solidify but actually continue to
flow very slowly under the influence of gravity.
- Supercritical Fluid
- A substance at temperature above its critical temperature.
- Supersaturated Solution
- A solution that contains a higher than saturation concentration of solute;
slight disturbance or seeding causes crystallization of excess solute.
- A heterogeneous mixture in which solute-like particles settle out of
solvent-like phase some time after their introduction.