Chemistry
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At the present time, Cyc's representation of scientific
chemistry is limited to certain basic relations between atoms,
molecules, and substances. Most representations of complex
substances in Cyc do not include chemical structures and
formulae, or the axioms to reason about them. Rather,
substances and their properties are represented at a more
"everyday" level: creation, destruction, changes, and
interactions are described and reasoned about, but the
underlying mechanisms are not usually considered.We have
resisted the temptation to assert many detailed, ready-made
axioms based on chemical reference material listing atomic
weights, electronegativity values, chemical formulae, etc.,
because devising the supporting theoretical axioms to use those
facts is neither easy nor of obvious value. Such is the case
with many fundamental theories in science: connecting them to
the real world is so hard that most scientific problems are
solved by invoking more specific rules which apply to different
kinds of situations.The following constants and the
representational techniques they embody may serve as a starting
point for more complete representations of chemical substances
as well as a more comprehensive chemical theory. For example,
the functional specification of types of atoms and nuclei can be
extended to cover isotopes.
Elements And Atoms
#$ElementStuff chemical elements
An instance of #$TangibleStuffCompositionType
and a specialization of #$InanimateThing.
Each instance of #$ElementStuff
is a piece of tangible stuff, composed of a quantity of
atoms, all of which are of the same chemical element. That
is, every atom in a given piece of #$ElementStuff
has the same number of protons in its atomic nucleus. For
example, all pieces of carbon (i.e. all instances of
#$Carbon) are instances of #$ElementStuff.
On the other hand, instances of #$Water, because they are
all constituted of both #$Hydrogen and #$Oxygen atoms, do
not belong to the collection #$ElementStuff.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$InanimateThing
direct generalization of:
#$UnalloyedMetal
#$ElementStuffTypeByNumberOfProtons types
of chemical element classified by number of protons
A collection of collections and a specialization of
#$ElementStuffType. Each instance of #$ElementStuffTypeByNumberOfProtons
is a specialization of #$ElementStuff
which is defined _only_ by the atomic composition of its
instances -- neither the isotopic composition or physical
state of the substances, nor any other additional feature,
determines membership in an instance of #$ElementStuffTypeByNumberOfProtons.
All that matters is that the instances of that collection
are entirely composed of atoms having a particular number of
protons in each atomic nucleus. Thus, the collection
#$Carbon is an instance of #$ElementStuffTypeByNumberOfProtons,
but neither the collection #$Diamond nor the collection
#$Graphite is (even though they are subcollections of
#$Carbon), because their members have additional qualifications.
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direct instance of: #$SecondOrderCollection
#$DisjointCollectionType
#$AtemporalNecessarilyEssentialCollectionType
direct specialization of:
#$ElementStuffType #$ChemicalSubstanceType
direct generalization of:
#$NobleGasElement
#$atomicNumber atomic
number (predicate that is functional in its second
argument) (functional predicate) (binary predicate)
This predicate relates an atomic number to an
element. (#$atomicNumber
ELEMENT INT) means that ELEMENT, an instance of #$ElementStuffTypeByNumberOfProtons,
has the #$PositiveInteger
INT for its atomic number. This means that any instance of
(#$AtomFn
ELEMENT) must have INT many protons (see #$Proton) in its
atomic nucleus (see #$AtomicNucleus).
For example, (#$atomicNumber
#$Carbon 6) means that every instance of (#$AtomFn #$Carbon)
has six protons in its nucleus.
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direct instance of: #$StrictlyFunctionalSlot
#$AtomFn atom fn
An instance of both #$CollectionDenotingFunction
and #$ReifiableFunction.
When applied to an instance ELEMENT-TYPE of
#$ElementStuffType, #$AtomFn returns
the collection of all atoms (see #$Atom) of
ELEMENT-TYPE. Each instance of the collection (#$AtomFn
ELEMENT-TYPE) is an atom with N protons in its atomic
nucleus, where N is the #$atomicNumber
(q.v.) of ELEMENT-TYPE. For example, (#$AtomFn #$Carbon)
is the collection of all carbon atoms, each of which has 6
protons in its nucleus. Additionally, each atom has a
#$massNumberOfAtom (which need not be same for all atoms of
the same #$ElementStuffType : see #$IsotopeFn).
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direct instance of: #$UnaryFunction #$CollectionDenotingFunction
#$ReifiableFunction
#$Individual
#$Atom atoms (inanimate
objects) (tangible things) (things with a location)
A specialization of #$ChemicalObject.
Each instance of #$Atom is a
microscopic-scale object with exactly one atomic nucleus
(see #$AtomicNucleus)
and some number of electrons (see #$Electron). A
typical instance of #$Atom has no net
charge, i.e., it has as many instances of #$Electron as it
does of #$Proton. For the
collection of atoms that do have non-zero charges, see #$AtomicIon.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$ChemicalObject
#$NucleusFn nucleus fn
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
#$NucleusFn is a
Cyc function, specifically a #$CollectionDenotingFunction.
#$NucleusFn
takes an instance of #$ElementStuffTypeByNumberOfProtons
(q.v.) as its single argument and returns a collection of
all the atomic nucleii belonging to element-stuff of that
type. Thus, (#$NucleusFn E)
denotes a subcollection of #$AtomicNucleus
whose elements all have the same number of protons. For
example, (#$NucleusFn
#$Carbon) is the collection of #$Carbon nuclei, each of
which has six protons.
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direct instance of: #$UnaryFunction #$CollectionDenotingFunction
#$ReifiableFunction
#$Individual
#$AtomicNucleus atomic nuclei
A specialization of #$MicroscopicScaleObject.
Each instance of #$AtomicNucleus
is an object composed of some definite number of instances
of #$Proton and
some definite number of instances of #$Neutron. Each
instance of #$Atom
has exactly one instance of #$AtomicNucleus
as a part.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$MicroscopicScaleObject
Sub
#$SubAtomicParticle subatomic particles
A specialization #$MicroscopicScaleObject
and #$InanimateObject-Natural.
Each instance of #$SubAtomicParticle
is a physical particle smaller than the smallest atom. Major
subcollections of #$SubAtomicParticle
include #$Electron, #$Proton, and #$Neutron.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$MicroscopicScaleObject #$InanimateObject-Natural
direct generalization of:
#$Nucleon
#$Electron electrons
A specialization of #$Lepton. Each instance of #$Electron is a
subatomic particle with an #$ElectricalCharge
of -1. Each instance of #$Atom consists of a
nucleus (see #$AtomicNucleus)
surrounded by a cloud of negatively charged electrons.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$Individual
#$Nucleon nucleons
A specialization of #$SubAtomicParticle.
Each instance of #$Nucleon is a
subatomic particle found in some atomic nucleus (see the
collection #$AtomicNucleus).
#$Nucleon
has two subcollections, #$Proton and #$Neutron. Every
instance of #$AtomicNucleus
is composed of some number of #$Nucleons.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$SubAtomicParticle
direct generalization of:
#$Neutron #$Proton
#$Proton protons
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A specialization of #$Nucleon. Each
instance of #$Proton is a
nucleon which has an #$ElectricalCharge
of +1.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$Nucleon
#$Neutron neutrons
A specialization of #$Nucleon. Each
instance of #$Neutron is a
nucleon with an electrical charge of 0.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$Nucleon
Chemical Compounds Molecules
#$ChemicalObject chemical objects
A specialization of #$MicroscopicScaleObject.
Each instance of #$ChemicalObject
is an object whose behavior is typically described in terms
of its outer cloud of #$Electrons.
Specializations of #$ChemicalObject
include the collections #$Atom, #$Molecule, and
#$Ion.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$MicroscopicScaleObject
direct generalization of:
#$Molecule #$Atom
#$Molecule molecules
A subcollection of #$ChemicalObject
and #$ComplexPhysicalObject. Each instance of #$Molecule is a
microscopic-scale object whose component atoms are all
chemically bonded to each other; typically, this means that
the atoms are covalently bonded. Examples: some instances of
#$Molecule,
including molecules of oxygen (O2), ozone (O3), water (H2O),
carbon monoxide (CO), carbon dioxide (CO2), etc., contain
covalently bonded atoms belonging to the collection
#$Oxygen. Some highly complex examples of #$Molecule are
those belonging to the collection #$DNAMolecule. See also #$MoleculeFn.
Note: #$Diamond and other macroscopic covalent solids are
excluded from belonging to #$Molecule by the
constraint that instances of #$Molecule are microscopic.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$ComplexPhysicalObject #$ChemicalObject
#$Ion ions
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of microscopic-scale objects; a subset
of #$ChemicalObject.
Every instance of #$Ion is an atom or
radical which has either a negative or positive net
electrical charge, due to having either more or fewer
electrons than there are protons in its nuclei. Note: atomic
ions violate Cyc's default assumption that instances of #$Atom have a net
electrical charge of zero, so #$Ion constitutes a
class of exceptions to that rule.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$ChemicalObject
#$ChemicalSubstanceType chemical substances
**COMMENT NOT REVIEWED**
A collection of collections and a specialization of
#$TangibleStuffCompositionType.
Each instance of #$ChemicalSubstanceType
is a specialization of #$PartiallyTangible
whose instances are defined _only_ by their chemical
composition -- not by their physical state or any other
property. Instances of #$ChemicalSubstanceType
can be of two varieties: (1) Collections whose instances are
completely uniform with each other in terms of chemical
composition; this includes (a) the chemical elements -- such
as #$Carbon, #$Oxygen, and #$Hydrogen -- which are instances
of #$ElementStuffTypeByNumberOfProtons
(thus, the latter is a specialization of #$ChemicalSubstanceType),
and (b) chemical compounds constituted of more than one
substance chemically bonded, e.g., #$Water, #$Caffeine, and
#$IronOxide, which are instances of
#$ChemicalCompoundTypeByChemicalSpecies (2) Substances which
have a general chemical specification, that is, whose
instances do not have exactly the same chemical composition
but fall within certain specifications, e.g., #$DNAStuff.
Note that collections that are _not_ instances of #$ChemicalSubstanceType
include collections of substances which have some component
which is of overriding significance in some context, so that
in everyday language such substances are frequently referred
to by the name of their important component (e.g.,
penicillin applied to a tablet containing penicillin), but
which have significant admixtures of other substances. Thus,
#$Penicillin is an instance of #$ChemicalSubstanceType,
but the collection of tablets containing penicillin and
including other ingredients is not. Also, specializations of
#$Mixture, such
as #$Lemonade, are _not_ instances of #$ChemicalSubstanceType,
because mixtures are determined by their physical state
rather than solely by their chemical composition.
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direct instance of: #$SiblingDisjointCollectionType
#$SecondOrderCollection
#$AtemporalNecessarilyEssentialCollectionType
direct specialization of:
#$TangibleStuffCompositionType
direct generalization of:
#$ElementStuffTypeByNumberOfProtons
#$MolecularStuff molecular stuff
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuff. Every instance of
#$MolecularStuff
is a portion of stuff composed of covalently-bonded
molecules. Thus, #$Water and #$DNAStuff are subcollections
of #$MolecularStuff;
each of their instances consists of covalently bonded
molecules. But instances of #$Salt-NaCl are not examples of
#$MolecularStuff.
Also, #$Oxygen is not a subcollection of #$MolecularStuff,
since #$Oxygen denotes anything composed of that element,
not just O2 (molecular oxygen) and O3 (ozone).
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$PartiallyTangible
#$MoleculeFn molecule fn
A function that takes as an argument an instance
CHEM-TYPE of #$ChemicalSubstanceType
and returns the collection of all molecules of CHEM-TYPE.
For example, (#$MoleculeFn
#$Water) is the collection of all water molecules.
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direct instance of: #$MacroRelation #$UnaryFunction
#$CollectionDenotingFunction
#$ReifiableFunction
#$Individual
#$MicroscopicScaleObject microscopic objects
A specialization of #$PartiallyTangible.
Each instance of #$MicroscopicScaleObject
is a partially tangible object which is so small that human
beings cannot perceive it, except (perhaps) with the use of
special devices such as #$Microscopes or
#$ElectronMicroscopes. Specializations of #$MicroscopicScaleObject
include #$Molecule, #$Atom, #$SubAtomicParticle,
#$Chloroplast, and #$Mitochondrion.
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direct instance of:
#$TemporalStuffType
direct specialization of:
#$PartiallyTangible
direct generalization of:
#$SubAtomicParticle
#$ChemicalObject
#$AtomicNucleus
#$CellPart
#$Microorganism
Metal
#$Metal metals
An instance of #$TangibleStuffCompositionType.
Every instance of #$Metal is a
tangible object having certain characteristic physical and
chemical properties. Instances of #$Metal are good
conductors of electricity and heat, and most instances of #$Metal are solids
at room temperature (although all instances of #$Mercury,
for example, are liquids at room temperature). Solid
instances of #$Metal have a shiny
luster, and are highly malleable. Specializations of #$Metal include
#$Mercury, #$Potassium, #$Brass, #$Lead, and #$Iron.
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direct instance of: #$ProductByGenericType #$TangibleStuffCompositionType
direct specialization of:
#$ElectricalConductor #$InorganicStuff
direct generalization of:
#$UnalloyedMetal
#$MetalAlloy
#$MetalAlloy alloys
A collection of tangible stuffs; a subcollection of
#$Metal. Each
instance of #$MetalAlloy is
a metallic stuff which is a homogeneous blend of at least
one part of #$UnalloyedMetal
with at least one other substance. #$MetalAlloy is
not a subcollection of #$Mixture,
because each instance of #$MetalAlloy is
defined not only by the amounts and kinds of its #$constituents,
but also (unlike a mixture) by the internal structures
formed during its creation. Furthermore, the creation
process is typically more complex than #$Mixing. Common
metal alloys include the instances of #$Bronze-Stuff,
#$Brass, and #$Steel. Note that #$GalvanizedMetal is _not_ a
subcollection of #$MetalAlloy,
because every instance of #$GalvanizedMetal has a coating of
some #$Zinc on its surface, and thus (unlike an alloy) the
components of galvanized metals are not homogenously
distributed throughout.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$SolidTangibleThing #$Mixture #$ArtificialMaterial #$Metal
#$UnalloyedMetal unalloyed metals
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuffs; a subcollection of
#$Metal.
Every instance of #$UnalloyedMetal
is a metal which is also an element, i.e., a substance of
unmixed chemical type. Thus, each subcollection of #$UnalloyedMetal
is a subcollection of both #$Metal and #$ElementStuff.
Examples of #$UnalloyedMetal
include #$Gold, #$Iron, #$Uranium, #$Antimony, #$Titanium,
and many more.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$Metal #$ElementStuff
#$NobleGasElement noble gases
A specialization of
ElementStuffTypeByNumberOfProtons. Each instance of #$NobleGasElement
is a type of element that does _not_ readily form compounds
with other types of elements. Instances of #$NobleGasElement
are highly stable, due to the fact that they have the
maximum number of electrons possible in their outer shell.
The six instances of #$NobleGasElement
are #$Helium, #$Neon, #$Argon, #$Krypton, #$Xenon, and #$Radon.
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direct instance of: #$SecondOrderCollection
direct specialization of:
#$ElementStuffTypeByNumberOfProtons
Chemical Reactions
#$ChemicalReaction chemical reactions
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of events; a subcollection of #$PhysicalTransformationEvent.
Each instance of #$ChemicalReaction
is an event in which two or more substances undergo a
chemical change, i.e., some portions of the substances
involved are transformed into different
#$ChemicalCompoundTypes. The transformations are brought
about by purely chemical (including biochemical) means which
affect chemical bonds between atoms in the molecules of
stuff, rather than by physical means, biological means, or
purposeful planning, etc. Examples of #$ChemicalReaction
: instances of #$CombustionProcess;
instances of #$Photosynthesis-Generic.
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direct instance of:
#$DefaultDisjointScriptType
#$TemporalObjectType
direct specialization of:
#$ChemicalInteraction #$PhysicalTransformationEvent
direct generalization of:
#$BiologicalMetabolismEvent
#$catalyst catalyst
(actor slot) (role) (extensional representation predicate)
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
The predicate #$catalyst
identifies the particular thing that acts as a catalyst in a
particular chemical reaction. (#$catalyst R X)
means that the #$ChemicalReaction
R has the particular quantity of substance X as a catalyst.
For example, every instance of #$Photosynthesis-Generic has
some portion of #$Chlorophyll as a catalyst; an amount of
#$Water may be a #$catalyst in
some #$OxidationProcess
of a #$Metal.
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direct instance of: #$IndividualLevelPredicate #$ActorSlot
direct specialization of: #$unchangedActors
Purity
#$PureFn pure fn
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
An instance of #$CollectionDenotingFunction.
(#$PureFn X)
denotes the subcollection of the #$ChemicalSubstanceType
X whose instances are chemically pure. Note that #$PureFn can be
applied only to instances of #$ChemicalSubstanceType
(such as #$Fructose or #$Water), but not to mixtures (such
as #$Air). See also #$PureSubstance.
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direct instance of: #$UnaryIntersectionFunction #$Individual
#$PureSubstance pure substances
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuffs. Each instance of
#$PureSubstance
is a chemically pure portion of stuff belonging to some
particular #$ChemicalSubstanceType
(e.g. #$Water or #$Cellulose). `Chemically pure' applies to
a piece of stuff which has no sub-portions that fail to
conform to the chemical composition of its (single) #$ChemicalSubstanceType.
In typical contexts, most common portions of a #$ChemicalSubstanceType
will not be instances of #$PureSubstance
. For example, a piece of pencil lead, though mostly carbon,
will not be an instance since it is not pure carbon and any
portion of ordinary tap water will contain too many
impurities. Many sub-portions of either a piece of pencil
lead or portion of tap water will fail to conform to the
chemical composition of either carbon or water. Some
instances of #$ChemicalSubstanceType
are subcollections of #$PureSubstance
in most contexts but not in all. In typical domestic
contexts, for example, a piece of ordinary distilled water
would be an instance of #$PureSubstance
. However, in a clean room or microchip manufacturing
context, ordinary distilled water would probably be
considerd impure (see #$ImpureCompound). In general, to
refer to a pure instance of a substance one can use the
function #$PureFn, e.g. (#$PureFn
#$Carbon). Note that #$PureFn has #$PureSubstance
as a #$resultGenl
. Since this kind of purity is relative to specified
chemical composition only, #$PureSubstance
(and #$PureFn)
does not pertain to mixtures in Cyc (such as #$Air). Cf. #$Mixture, #$ChemicalSubstanceType.
See also #$PureSubstanceType
and #$ImpureCompound.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$InanimateThing
#$PureSubstanceType types
of pure substance
An instance of #$SecondOrderCollection. Each
instance of #$PureSubstanceType
is both a specialization of #$PureSubstance
(q.v.) and a specialization of some instance of #$ChemicalSubstanceType
(q.v.). Each instance of #$PureSubstanceType
is characterized by the properties of the instance of #$ChemicalSubstanceType
of which it is a specialization, and by the fact that each
of its instances is chemically pure.
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direct instance of: #$SecondOrderCollection
direct specialization of:
#$TangibleStuffCompositionType
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