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

This template, {{chem}}, serves to simplify the writing of chemical formulae. For example,

{{chem|H|2|O}}

will yield:

H
₂O

Algebraic expressions are rendered as subscripts (but must not contain upper case letters).

{{chem|C|''n''|H|2''n'' + 2}}

gives

C
_nH
_2n + 2

Ion charge superscripts (for: +/-) are also supported:

{{chem|H|3|O|+}}

yields a "+" as superscript:

H
₃O⁺

Simultaneous subscripts/superscripts are automatically handled (use a hyphen for the minus sign):

{{chem|SO|4|2-}}

gives "2-" as superscript:

SO²⁻
₄

Note

The hyphen is converted to a true minus sign.

The first parameter can be used for mass number.

{{chem|4|He}}

gives:

⁴
He

The first two parameters can be used for mass number and atomic number.

{{chem|4|2|He}}

gives:

⁴
₂He

Note

Only the first two parameters can handle two consecutive plain numbers (i.e. without a plus sign or a hyphen (+ or -) following). Otherwise the template will loop.

The optional parameter link changes the formula into a link. For example:

{{chem|link=water|H|2|O}}

will yield:

H
₂O

For linking individual elements can be linked in the following manner.

{{chem|[[Hydrogen|H]]|2|[[Oxygen|O]]}} 

gives

H
₂O

• To include "=" in the formula, use "=" For example, "{{chem|CH|2|=CH|2}}" yields CH
  ₂=CH
  ₂.
  • Or, don't use this template. For example, "CH₂=CH₂" yields CH₂=CH₂.
  • Or, {{chem|CH|2}}={{chem|CH|2}}, which yields CH
    ₂=CH
    ₂.
• To include "≡" in the formula, use "≡" For example, "{{chem|HC≡CH}}" yields HC≡CH.
• The template accepts up to twenty parameters in addition to link.
• This template uses {{su}}.