represents a chemical whose qualifiers quali have values of vali.


represents a chemical quantified by quantity.


  • Possible forms for chemical include:
  • Atom[]an atom
    BioSequence[]a biomolecular sequence
    ChemicalFormula[]a molecular entity with the given formula
    Entity[]a chemical entity
    ExternalIdentifier[]an external identifier
    Molecule[]a molecule
    "identifier"a systematic chemical name, SMILES or InChI string
  • Chemical entities include "Chemical", "Element", "Isotope", "Mineral" and "Protein".
  • Typical quali qualifiers include:
  • "Amount"amount of substance
    "AtomCount"number of atoms
    "MoleculeCount"number of molecules
    "Phase"phase of matter
  • The quali can be physical quantity names, a QuantityVariable expression or a "PhysicalQuantity" Entity.
  • Properties "prop" of a ChemicalInstance obtained by ChemicalInstance[]["prop"] include:
  • "Amount"amount of substance
    "AtomCount"number of atoms
    "Chemical"chemical object
    "MoleculeCount"number of molecules
    "Quantity"quantity object
  • ChemicalInstance[chemical,assoc]["prop"] will return the value for the specified property in assoc.


open allclose all

Basic Examples  (2)

Represent a solid silver nanoparticle containing 40 atoms:

Represent a measured amount of tin(IV) oxide using a milligram balance:

An equivalent specification:

Scope  (10)

Chemical Objects  (6)

Represent a gold nanoparticle containing 30 atoms:

Represent 3 milligrams of a DNA sequence:

Represent 3 mL of a new chemical with an empirical formula of :

Represent 50 micrograms of plutonium-239:

Represent solid uranium(VI) oxide using an ExternalIdentifier:

Represent 6 millimoles of tungsten hexamethyl:

Properties  (4)

Extract the chemical:

Extract the quantity:

Compute the quantity corresponding to an extensive physical property:

Get a chemical property using any qualifying data that is present:

Generalizations & Extensions  (2)

Compute the volume symbolically when the density is unknown:

Compute the amount of substance symbolically:

Applications  (1)

Compare the number of atoms in 2 mg of each stable isotope of tin:

Possible Issues  (1)

Properties of a chemical at a nonstandard temperature and pressure may be unavailable:

Wolfram Research (2022), ChemicalInstance, Wolfram Language function,


Wolfram Research (2022), ChemicalInstance, Wolfram Language function,


Wolfram Language. 2022. "ChemicalInstance." Wolfram Language & System Documentation Center. Wolfram Research.


Wolfram Language. (2022). ChemicalInstance. Wolfram Language & System Documentation Center. Retrieved from


@misc{reference.wolfram_2024_chemicalinstance, author="Wolfram Research", title="{ChemicalInstance}", year="2022", howpublished="\url{}", note=[Accessed: 24-June-2024 ]}


@online{reference.wolfram_2024_chemicalinstance, organization={Wolfram Research}, title={ChemicalInstance}, year={2022}, url={}, note=[Accessed: 24-June-2024 ]}