Template:Chem2/doc

This is a documentation subpage for Template:Chem2. It may contain usage information, categories and other content that is not part of the original template page.

This template is used on approximately 6,500 pages and changes may be widely noticed. Test changes in the template's /sandbox or /testcases subpages, or in your own user subpage. Consider discussing changes on the talk page before implementing them.

This template uses Lua: Module:Chem2 (sandbox)

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.

Use

Formula punctuation

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} N

The closing bracket {..} of input and end of template brackets }}.

• Solutions:

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

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

add a space: {{chem2|..{..} }}

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

Formulas, charges, 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 mu:

• {{chem2|W(CO)3(PiPr3)2(\h{2}H2)}} → W(CO)₃(PiPr₃)₂(η²-H₂)
• {{chem2|W(CO)3(PiPr3)2(\h{2}H2)|auto=yes}} → W(CO)₃(PiPr₃)₂(η²-H₂)

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 |link=<wiki pagename>:

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

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

• {{chem2|3[[hydrogen|H2]] + 2[[nitrogen|N2]] <-> 2[[ammonia|NH3]]}} → 3H₂ + 2N₂ ⇌ 2NH₃

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

Use |auto=yes to link from the first occurrence of each element symbol, and some functional-group symbols such as Ph

• {{chem2|CH3CH2CH3CBrFCIClCH3|auto=yes}} → CH₃CH₂CH₃CBrFCIClCH₃

Link functional groups

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

• {{chem2|R\-[[COOH]]}} → R-
  COOH
• {{chem2|[[CH3]]C[[R]]2[[I]]}} → CH₃CR₂I
• In particular H2O links to water of crystallization in {{chem2|CuSO4 * 5 [[H2O]]}} → 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

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

• {{chem2|C_{''n''}H_{2''n'' + 2}|}} → C_nH_2n + 2
• (chem: {{chem|C|''n''|H|2''n'' + 2}} → 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}} → ¹³CO₂
• {{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{CoCl₂})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.)

TemplateData

Tracking

• Category:Pages using Chem2 with parameter issues (0)

See also

• {{Chem}}
• <chem>:
  WP:MATHCHEM
  — by TeX