8.2 KiB
| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Glossary of chemistry terms | 17/20 | https://en.wikipedia.org/wiki/Glossary_of_chemistry_terms | reference | science, encyclopedia | 2026-05-05T07:59:20.572989+00:00 | kb-cron |
retort A laboratory apparatus used for the distillation or dry distillation of chemical substances, traditionally consisting of a spherical vessel with a long, downward-pointing neck that conducts the condensed vapors produced by distillation into a separate collection vessel.
reversible reaction A chemical reaction that can proceed in either direction depending on the reaction conditions, i.e. from reactants to products or from products to reactants, especially implying one in which both conversions occur simultaneously. Contrast irreversible reaction.
rotamer
round-bottom flask
rust
== S ==
s-block The collective name for the elements in Groups 1 and 2 of the periodic table (the alkali and alkaline metals), as well as hydrogen and helium.
saline solution A common term for a solution of sodium chloride (NaCl) dissolved in water (H2O).
salt Any ionic compound composed of one or more anions and one or more cations.
salt bridge A device used to connect reduction with oxidation half-cells in an electrochemical cell.
saturation
Schrödinger equation A quantum state equation which represents the behaviour of an electron around an atom.
scintillation A burst of luminescence of short duration produced by an individual energetically excited particle as it releases energy.
second-order reaction
semiconductor An electrically conductive solid whose degree of conductivity lies somewhere between that of a conductor and that of an insulator.
serial dilution
side chain A chemical substituent group that is attached to the core part or "backbone" of a larger molecule, especially an oligomeric or polymeric hydrocarbon chain that branches off of the longer primary chain of a macromolecule. The term is most commonly encountered in biochemistry and organic chemistry.
single bond A bond that involves the sharing of one pair of electrons.
skeletal formula
sol A suspension of solid particles in a liquid. Artificial examples include sol-gels.
solid One of the four fundamental states of matter, characterized by relatively low-energy particles packed closely together in rigid structures with definite shape and volume. See Young's modulus.
solid-phase extraction (SPE)
solubility The property of a solid, liquid, or gaseous solute to dissolve in a solid, liquid, or gaseous solvent. It is typically expressed as the proportion of solute dissolved in the solvent in a fully saturated solution.
solubility product (
K
s
{\textstyle K_{{\ce {s}}}}
or
K
sp
{\textstyle K_{{\ce {sp}}}}
) A measure of the solubility of an ionic solute, expressed as the arithmetic product of the concentrations of its ions in a fully saturated solution, with respect to the solute's particular dissociation equilibria and the particular ions present. For a dissociation equilibrium
A
x
B
y
(
s
)
⇋
x
A
(
a
q
)
+
+
y
B
(
a
q
)
−
{\textstyle \mathrm {{A_{x}}{B_{y}}_{(s)}} \leftrightharpoons \mathrm {xA_{(aq)}^{+}} +\mathrm {yB_{(aq)}^{-}} }
, the solubility product of the ionic solute
A
x
B
y
{\textstyle \mathrm {A_{x}} \mathrm {B_{y}} }
is given by
K
s
=
[
A
+
]
x
[
B
−
]
y
{\textstyle K_{{\ce {s}}}=[{\ce {A+}}]^{x}[{\ce {B-}}]^{y}}
, where
[
A
+
]
{\textstyle [{\ce {A+}}]}
and
[
B
−
]
{\textstyle [{\ce {B-}}]}
are the concentrations of the solute's ionic constituents in a saturated solution. The solubility product is derived from and functions like the equilibrium constant of dissociation, though unlike an equilibrium constant it is not dimensionless. If the product of ionic concentrations in a solution exceeds the solubility product, then precipitation occurs.
solute The part of a solution that is dissolved into the solvent. For example, sodium chloride (NaCl) is the solute in a solution of saline water.
solution A homogeneous mixture made up of multiple substances generally referred to as solutes and solvents.
solvated electron
solvation Any stabilizing interaction of a solute with a solvent, or a similar interaction between a solvent and groups of an insoluble material (e.g. the ionic groups of an ion-exchange resin). Such interactions generally involve electrostatic forces and van der Waals forces, as well as compound-specific effects such as hydrogen bonding. See also dissolution.
solvation shell
solvent The part of a solution that dissolves the solute. For example, water (H2O) is the solvent in a solution of saline water.
sonication Also ultrasonication. The process of irradiating a substance with sound energy, usually at ultrasound (>20 kHz) frequencies, in order to agitate the particles in a sample for various purposes, such as increasing the rate of a chemical reaction or preparing vesicles in mixtures of surfactants and water.
spatial isomer See stereoisomer.
specific heat capacity (cp) Also massic heat capacity. The heat capacity of a sample of a substance divided by the mass of the sample. Informally, it is the amount of heat that must be added to one unit of mass of the substance in order to cause an increase of one unit in temperature. The SI unit of specific heat capacity is joule per kelvin per kilogram (J/K/kg). Specific heat capacity often varies with temperature and with each state of matter.
spectrochemistry
spectrometry See mass spectrometry.
spectroscopy The study of radiation and matter, such as X-ray absorption and emission spectroscopy.
standard solution
standard conditions of temperature and pressure (STP) A standardisation of ambient temperature and pressure used in order to easily compare experimental results. Standard temperature is 25 degrees Celsius (°C) and standard pressure is 100.000 kilopascals (kPa). Standard conditions are often denoted with the abbreviation STP or SATP.
state of matter The condition of matter existing in a distinct, homogeneous, macroscopic form. Solid, liquid, gas, and plasma are the four traditional states of matter and the most well-known. See also phase.
stepwise reaction
stereochemistry
stereogenic center Also stereocenter.
stereoisomer Also spatial isomer. An isomer which possesses an identical chemical composition but which differs in the spatial arrangement of its atoms.