Template:Chem2: Difference between revisions

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Module:Chem2

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This template should not be used in citation templates such as Citation Style 1 and Citation Style 2, because it includes markup that will pollute the COinS metadata they produce; see Wikipedia:COinS.

{{chem2}} is a template used to format a chemical formula or equation.

When displaying a chemical equation on its own line, it should be indented using a colon (:) and not centered. (For further information, see MOS:CHEMINDENT.)

Use

Formula punctuation

Symbol	Gives	Example	Output
`\s`	−	`{{chem2\|CH3\sCH3}}`	CH₃−CH₃
`\d`	=	`{{chem2\|CH2\dCH2}}`	CH₂=CH₂
`\t`	≡	`{{chem2\|HC\tCH}}`	HC≡CH
`\q`	≣	`{{chem2\|[Cl4Re\qReCl4](2−)}}`	[Cl₄Re≣ReCl₄]²⁻
`\-`	-	<syntaxhighlight lang="tex" inline>A-B</syntaxhighlight>	A-B
`\\`	\	<syntaxhighlight lang="tex" inline>C\D</syntaxhighlight>	C\D
`\h`	η	<syntaxhighlight lang="tex" inline>η</syntaxhighlight>	η
`\h{1}`	η¹-	<syntaxhighlight lang="tex" inline>η¹-</syntaxhighlight> § {}	η¹-
`\m{1}`	μ₁-	<syntaxhighlight lang="tex" inline>μ₁-</syntaxhighlight>	μ₁-
`->`	→	`{{chem2\|2H2 + O2 -> 2H2O}}` § {}	2H₂ + O₂ → 2H₂O
`<->`	⇌	`{{chem2\|K<->L}}`	K ⇌ L
`*`	·	`{{chem2\|CoCl2*6H2O}}`	CoCl₂·6H₂O
`\*`	*	<syntaxhighlight lang="tex" inline>Cp*₂Fe</syntaxhighlight>	Cp*₂Fe
`_{}`	_subscript	<syntaxhighlight lang="wikitext" inline>C_nH_2n+2</syntaxhighlight> § {}	C_nH_2n+2
`^{}`	^superscript	`{{chem2\|^{13}CH4}}`	¹³CH₄
`∇`	∇	<syntaxhighlight lang="wikitext" inline>∇</syntaxhighlight>	∇
`( )`	( )	`{{chem2\|R\sCH(OH)CN}}`	R−CH(OH)CN

End }-bracket issue

When input ends correctly with a }-bracket, like with A_{x}H_{1-x}, the final }-brackets are technically mixed up:

{{chem2|A_{x}H_{1-x}}} → A_xH_{−1x} Red X

The closing bracket <syntaxhighlight lang="text" class="" style="" inline="1">}</syntaxhighlight> of input and end of template brackets <syntaxhighlight lang="text" class="" style="" inline="1">}}</syntaxhighlight> are interpreted by Wikipedia software in reversed order.

Solutions:

Empty pipe: {{chem2|...{...}|}} (empty parameter #2)

Parameters numbers 1 and 2 (empty): {{chem2|1=...{...}|2=}}

Space: {{chem2|...{...} }}

Nowiki tag: {{chem2|...{...}<nowiki/>}}

Escape the last set of brackets: {{chem2|A_{x}H_{{(}}1-x{{)}}}}

Result: {{chem2|A_{x}H_{1-x}|}} → A_xH_1−x Green tick

Formulas, charges, and equations

Formulas (without charge) are just written:

{{chem2|CH3(CH2)5CH3}} → CH₃(CH₂)₅CH₃
{{chem2|Fe3S2(CO)9}} → Fe₃S₂(CO)₉
{{chem2|C_{''n''}H_{2''n''+2}|}} → C_nH_2n+2

Charges are written inside parentheses:

{{chem2|SO4(2-)}} → SO2−4
{{chem2|S19(2+)}} → S2+19

Charges +1 and −1 can be written plain:

{{chem2|Na+}} → Na⁺
{{chem2|O2-}} → O−2

same as {{chem2|O2(-)}} → O−2

Chemical equations:

{{chem2|2 S + 3 O2 + 2 H2O -> 2 H2SO4}} → 2 S + 3 O₂ + 2 H₂O → 2 H₂SO₄
{{chem2|2S + 3O2 + 2H2O -> 2H2SO4}} → 2S + 3O₂ + 2H₂O → 2H₂SO₄

The arrows can be written as -> or just →. All characters (and unicode markup) are valid input except \, = (Mediawiki use it), _ and - (endash etc.)

{{chem2|2 H2(g) + O2(g) -> 2H2O(g)|}} → 2 H₂(g) + O₂(g) → 2H₂O(g)
{{chem2|NH2RCHCO2H <-> NH3+RCHCO2-}} → NH₂RCHCO₂H ⇌ NH+3RCHCO−2

Hapticity and bridging ligands:

{{chem2|(\h{5}Cp)FeCO(\m{2}CO)FeCO(\h{5}Cp)}} → (η⁵-Cp)FeCO(μ₂-CO)FeCO(η⁵-Cp)
{{chem2|(\h{5}Cp)FeCO(\m{2}CO)FeCO(\h{5}Cp)|auto=yes}} → (η⁵-Cp)Fe C O(μ₂-CO)FeCO(η⁵-Cp)

Wikilinks

As of March 2023^[update], {{chem2}} should not be used inside wikilinks; this can cause erratic failures to properly render sub/superscripts in other invocations on the same page. Instead, use the following options.

Whole formula link

Link the whole formula with <syntaxhighlight lang="wikitext" inline style="display: none;" />|link=<wiki pagename>:

{{chem2|FeCl3|link=Iron(III) chloride}} → FeCl₃

Or use wikilink brackets in input like [[ammonia|NH3]]:

<syntaxhighlight inline="1" lang="wikitext">{{chem2|3H2 + 2N2 <-> 2NH3}}</syntaxhighlight> → 3H₂ + 2N₂ ⇌ 2NH₃

Link each element (C, Hg) and generic element code (R, X)

Use <syntaxhighlight lang="wikitext" inline style="display: none;" />|auto=yes to link from the first occurrence of each element symbol, and some functional-group symbols such as Ph

{{chem2|CH3CH2CH3CBrFCIClCH3|auto=yes}} → C H₃CH₂CH₃CBr FCI ClCH₃

Link functional groups

Some common groups are recognized and linked if you wikilink them using [[ ]]

<syntaxhighlight inline="1" lang="wikitext">{{chem2|R\-COOH}}</syntaxhighlight> → R-COOH
<syntaxhighlight inline="1" lang="wikitext">{{chem2|CH3CR2I}}</syntaxhighlight> → CH₃CR₂I
In particular H2O links to water of crystallization in <syntaxhighlight inline="1" lang="wikitext">{{chem2|CuSO4 * 5 H2O}}</syntaxhighlight> → CuSO₄ · 5 H₂O, because a link to water is generally unnecessary.

You can link to any article even if chem2 is unaware of it:

{{chem2|[[C6H5NH2]]}} → C₆H₅NH₂

To change the default link:

{{chem2|[[water|H2O]]}} → H₂O

All recognised symbols and codes

All link targets recognised by {{chem2}} (elements, general codes, functional groups)

Elements and element-style symbols

These may be automatically linked or used as if they were redirects.

Symbol	Link target
Ac	Actinium
Ag	Silver
Al	Aluminium
Am	Americium
Ar	Argon
As	Arsenic
At	Astatine
Au	Gold
B	Boron
Ba	Barium
Be	Beryllium
Bh	Bohrium
Bi	Bismuth
Bk	Berkelium
Bn	Benzyl group
Br	Bromine
Bu	Butyl group
Bz	Benzoyl group
C	Carbon
Ca	Calcium
Cd	Cadmium
Ce	Cerium
Cf	Californium
Cl	Chlorine
Cm	Curium
Cn	Copernicium
Co	Cobalt
Cp	Cyclopentadienyl
Cr	Chromium
Cs	Caesium
Cu	Copper
D	Deuterium
Db	Dubnium
Ds	Darmstadtium
Dy	Dysprosium
Er	Erbium
Es	Einsteinium
Et	Ethyl group
Eu	Europium
F	Fluorine
Fe	Iron
Fl	Flerovium
Fm	Fermium
Fr	Francium
Ga	Gallium
Gd	Gadolinium
Ge	Germanium
H	Hydrogen
He	Helium
Hf	Hafnium
Hg	Mercury (element)
Ho	Holmium
Hs	Hassium
I	Iodine
In	Indium
Ir	Iridium
K	Potassium
Kr	Krypton
La	Lanthanum
Li	Lithium
Ln	Lanthanide
Lr	Lawrencium
Lu	Lutetium
Lv	Livermorium
Mc	Moscovium
Md	Mendelevium
Me	Methyl group
Mg	Magnesium
Mn	Manganese
Mo	Molybdenum
Mt	Meitnerium
N	Nitrogen
Na	Sodium
Nb	Niobium
Nd	Neodymium
Ne	Neon
Nh	Nihonium
Ni	Nickel
No	Nobelium
Np	Neptunium
Nu	Nucleophile
O	Oxygen
Og	Oganesson
Os	Osmium
P	Phosphorus
Pa	Protactinium
Pb	Lead
Pd	Palladium
Ph	Phenyl group
Pm	Promethium
Pn	Pentyl group
Po	Polonium
Pr	Praseodymium
Pt	Platinum
Pu	Plutonium
R	Substituent
Ra	Radium
Rb	Rubidium
Re	Rhenium
Rf	Rutherfordium
Rg	Roentgenium
Rh	Rhodium
Rn	Radon
Ru	Ruthenium
S	Sulfur
Sb	Antimony
Sc	Scandium
Se	Selenium
Sg	Seaborgium
Si	Silicon
Sm	Samarium
Sn	Tin
Sr	Strontium
T	Tritium
Ta	Tantalum
Tb	Terbium
Tc	Technetium
Te	Tellurium
Tf	Trifluoromethylsulfonyl group
Th	Thorium
Ti	Titanium
Tl	Thallium
Tm	Thulium
Ts	Tennessine
U	Uranium
V	Vanadium
W	Tungsten
X	Halogen
Xe	Xenon
Y	Yttrium
Yb	Ytterbium
Zn	Zinc
Zr	Zirconium

Groups

These must be linked manually; they work as if they were redirects.

Symbol	Link target
CH3	Methyl group
CO3	Carbonate
COOH	Carboxyl group
ClO	Hypochlorite
ClO2	Chlorite
ClO3	Chlorate
ClO4	Perchlorate
H2O	Water of crystallization
H3O	Hydronium
NH2	Amine group
NH4	Ammonium
NO3	Nitrate
PO3	Phosphite
PO4	Phosphate
SH	Thiol group
SO3	Sulfite
SO4	Sulfate
SeH	Selenol group

Examples and tests

(The first "→" in each example is not part of the output; it separates the example from its output.)

{{chem2|[Cl4Re\qReCl4](2-)|}} → [Cl₄Re≣ReCl₄]²⁻
{{chem2|NH2RCHCO2H <-> NH3+RCHCO2−}} → NH₂RCHCO₂H ⇌ NH+3RCHCO−2

{{chem2|\\hallo}} → \hallo
{{chem2|H3CC\tCH <-> H2C\dC\dCH2}} → H₃CC≡CH ⇌ H₂C=C=CH₂
{{chem2|4 NH3 + 5 O2 -> 4 NO + 6 H2O}} → 4 NH₃ + 5 O₂ → 4 NO + 6 H₂O

{{chem2|H2O → H2O}} → H₂O → H₂O
{{chem2|H2O(l) -> H2O(g)}} → H₂O(l) → H₂O(g)

{{chem2|4 NH3 + 5 O2 → 4 NO + 6 H2O}} → 4 NH₃ + 5 O₂ → 4 NO + 6 H₂O
{{chem2|4NH3 + 5O2 → 4NO + 6H2O}} → 4NH₃ + 5O₂ → 4NO + 6H₂O
{{chem2|2Mn2(+)}} → 2Mn+2
{{chem2|2Mn2(+) + 3H2O}} → 2Mn+2 + 3H₂O
{{chem2|Mn–}} → Mn⁻

{{chem2|Mn2(2-)}} → Mn2−2
{{chem2|Mn2☃+}} → Mn₂☃⁺;
{{chem2|Mn2(2☃–)}} → Mn₂(₂☃⁻)
{{chem2|Mn2(+)}} → Mn+2
{{chem2|Mn2+}} → Mn+2
{{chem2|Mn2(-)}} → Mn−2
{{chem2|Mn2-}} → Mn−2

<syntaxhighlight inline="1" lang="wikitext">{{chem2|C_{n}H_{2n + 2}|}}</syntaxhighlight> → C_nH_2n + 2
(chem: <syntaxhighlight inline="1" lang="wikitext">{{chem|C|n|H|2n + 2}}</syntaxhighlight> → C
_nH
_2n + 2
{{chem2|C_{abc}|}} → C_abc
{{chem2|CoCl2*1.5H2O}} → CoCl₂·1.5H₂O
{{chem2|Cu2C2*H2O}} → Cu₂C₂·H₂O

Special

{{chem2|[Me2Al(\m{2}Me)]2}} → [Me₂Al(μ₂-Me)]₂
{{chem2|^{13}CO2}} → ¹³CO₂
{{chem2|^{13}CO2|auto=yes}} → ¹³C O₂
{{chem2|\h{5}(C5H5)2TiCl2}} → η⁵-(C₅H₅)₂TiCl₂
(bad) {{chem2|\h{5}\s(C5H5)2TiCl2}} → η⁵-−(C₅H₅)₂TiCl₂
{{chem2|CH2\dCH2\sCH2\sC\tCH\qMn}} → CH₂=CH₂−CH₂−C≡CH≣Mn

{{chem2|RC(OR')3}} → RC(OR')₃
{{chem2|C\\C}} → C\C
{{chem2|C2*NH3}} → C₂·NH₃
{{chem2|C2*2NH3}} → C₂·2NH₃
{{chem2|C1.2H3.5}} → C_1.2H_3.5

{{chem2|\b\bAbC\e\e}} → AbC
{{chem2|C2(μ\-C)}} → C₂(μ-C)

{{chem2|SO4(2-)}} → SO2−4
{{chem2|2Mn2(2+)}} → 2Mn2+2
{{chem2|CH3-CH2-OH}} → CH−3CH−2OH
{{chem2|[ZnCl4]-}} → [ZnCl₄]⁻
{{chem2|[ZnCl4](2-)}} → [ZnCl₄]²⁻
{{chem2|((H2O)5{CoCl2})2|auto=yes}} → ((H₂O)₅{Co Cl₂})₂
{{chem2|Si(OH)4}} → Si(OH)₄

{{chem2|Cu2C2*H2O|auto=yes}} → Cu₂C₂·H₂O
{{chem2|Cu2C2*2H2O}} → Cu₂C₂·2H₂O
{{chem2|CuSO*2H2O}} → CuSO·2H₂O
{{chem2|CuSO4*15H2O}} → CuSO₄·15H₂O
{{chem2|CuSO4(H2O)5}} → CuSO₄(H₂O)₅
{{chem2|H+ + OH- → H2O}} → H⁺ + OH⁻ → H₂O
{{chem2|H → O}} → H → O

{{chem2|ZxPo4}} → ZxPo₄ Unknown element.
{{chem2|((Na)Cl}} → ((Na)Cl Too many "(".
{{chem2|Si(OH))4}} → Si(OH))₄ Too many ")".
{{chem2|Si&[[☃]]Si}} → Si&☃Si
{{chem2|1=CH2=CH2}} → CH₂=CH₂

More

{{chem2|Cl2O6|link=dichlorine hexoxide}} → Cl₂O₆
{{chem2|[Fe(Phen)(Phen)3](2+)}} → [Fe(Phen)(Phen)₃]²⁺
{{chem2|[Fe(Phen)(Phen)3](2+)|auto=yes}} → [Fe(Phen)(Phen)₃]²⁺
{{chem2|[C2O2](2+)}} → [C₂O₂]²⁺
{{chem2|SI4|link=Tomato}} → SI₄
{{chem2|H2SO4+}} → H₂SO+4
{{chem2|Mn-}} → Mn⁻
{{chem2|Mn22+}} → Mn+22, {{chem2|Mn22-}} → Mn−22
{{chem2|Mn(2+)}} → Mn²⁺
{{chem2|Mn2(+)}} → Mn+2
{{chem2|Mn(22-)}} → Mn²²⁻
{{chem2|Mn3(22-)}} → Mn22−3
{{chem2|Mn(22+)}} → Mn²²⁺
{{chem2|Mn2(22+)}} → Mn22+2
{{chem2|Mn2(2+)}} → Mn2+2
{{chem2|Mn22(2+)}} → Mn2+22

Chem vs. chem2

{{chem|(CH|3|)|2|CO}} → (CH
₃)
₂CO
{{chem2|(CH3)2CO}} → (CH₃)₂CO
{{chem|H|2|+}} → H⁺
₂
{{chem2|H2+}} → H+2

Predefined codes (groups etc.)

Predefined codes
code	target article	`{{chem2\|code}}`	type	note
A. Groups etc with element-like names
Bz	Benzoyl group	Bz	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
Et	Ethyl group	Et	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
Ln	Lanthanide	Ln	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
Nu	Nucleophile	Nu	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
Ph	Phenyl group	Ph	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
R	Substituent	R	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
T	Tritium	T	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
Tf	Trifluoromethylsulfonyl group	Tf	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
X	Halogen	X	A: wl <syntaxhighlight lang="wikitext" inline style="display: none;" />`\|auto=yes`
B. Groups which are redirected from their normal target if wikilinked; never autolinked.
CH3	Methyl group	CH₃	B: wl `\|..[[code]]..`
CO3	Carbonate	CO₃	B: wl `\|..[[code]]..`
COOH	Carboxyl group	COOH	B: wl `\|..[[code]]..`
ClO	Hypochlorite	ClO	B: wl `\|..[[code]]..`
ClO2	Chlorite	ClO₂	B: wl `\|..[[code]]..`
ClO3	Chlorate	ClO₃	B: wl `\|..[[code]]..`
ClO4	Perchlorate	ClO₄	B: wl `\|..[[code]]..`
H2O	Water of crystallization	H₂O	B: wl `\|..[[code]]..`
H3O	Hydronium	H₃O	B: wl `\|..[[code]]..`
NH2	Amine group	NH₂	B: wl `\|..[[code]]..`
NH4	Ammonium	NH₄	B: wl `\|..[[code]]..`
NO3	Nitrate	NO₃	B: wl `\|..[[code]]..`
PO3	Phosphite	PO₃	B: wl `\|..[[code]]..`
PO4	Phosphate	PO₄	B: wl `\|..[[code]]..`
SH	Thiol group	SH	B: wl `\|..[[code]]..`
SO3	Sulfite	SO₃	B: wl `\|..[[code]]..`
SO4	Sulfate	SO₄	B: wl `\|..[[code]]..`
SeH	Selenol group	SeH	B: wl `\|..[[code]]..`

TemplateData

This is the TemplateData for this template used by TemplateWizard, VisualEditor and other tools. See a monthly parameter usage report for Template:Chem2 in articles based on its TemplateData.

TemplateData for Chem2

Formats a chemical formula or equation using mhchem code. See template documentation for details on how it works.

Template parameters
Parameter		Description	Type	Status
Formula	`1`	The chemical formula or equation in mhchem, which can also be hyperlinked manually. See template documentation for how this works. Example 5HS- + 8NO3- + 3H+ -> 5SO4(2-) + 4N2 + 4H2O + 40e-	String	suggested
Autolinked?	`auto`	Hyperlink every first instance of chemical elements, functional groups, and other generic element codes. Default no	Boolean	optional
Whole formula link	`link`	Hyperlink the entire formula or equation to a given article page.	Page name	optional

Tracking

Category:Pages using Chem2 with parameter issues (0)

Revision as of 11:17, 21 March 2023 (view source) Wikipedia>Paine Ellsworth (per edit request on talk page - bugfix - add "auto, link=" parameter)		Latest revision as of 13:57, 12 August 2026 (view source) Maxisnt (talk \| contribs) m (1 revision imported)
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