Fyrimynd:Chem molar mass/format

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This template calculates the molecular mass (or molar mass) of a chemical compound. It is designed to be embedded in infoboxes {{Drugbox}} and {{Chembox}}, but it can be used in-line just as well.

Parameters

Use chemical symbols to compose the molecular formula: {{Chem molar mass|H=2|O=1}} (for H₂O) → 18,02 g·mol⁻¹

|round= by default the calculated number is rounded to 2 decimals.

|round=no will show all decimals:

{{Chem molar mass|Be=1|round=no}} → 9.0121831 g·mol⁻¹

|round=a number will round to that number of decimals

{{Chem molar mass|Be=1|round=4}} → 9,0122 g·mol⁻¹

|unit= changes the unit for the calculated result. The default unit is g·mol⁻¹.

{{Chem molar mass|H=2|O=1|unit=gram per mole}} → 18,02 gram per mole

The next parameters will always show:
|fixed= to enter a fixed (predefined) value+unit. It will overwrite any calculated value+unit.

|ref=<ref>some source</ref> will add the reference right after the unit.

|comment=Any textis added as a suffix, after a space and unedited (no brackets added etc.).

Example:

{{Chem molar mass|fixed=234.56 g/mol|ref=<ref>Some source</ref>|comment=My Comment}} → 234.56 g/mol^[1] My Comment

|sortable=yes, for use in sortable tables: will add a hidden sortable number, and omits the unit (see table below).

Blank parameter list

{{Chem molar mass
| round   =
| unit    =
| fixed   =
| ref     =
| comment =
| sortable=
| catname =
}}

{{Chem molar mass
<!-- 118 chemical symbols: -->|H= |He= |Li= |Be= |B= |C= |N= |O= |F= |Ne= |Na= |Mg= |Al= |Si= |P= |S= |Cl= |Ar= |K= |Ca= |Sc= |Ti= |V= |Cr= |Mn= |Fe= |Co= |Ni= |Cu= |Zn= |Ga= |Ge= |As= |Se= |Br= |Kr= |Rb= |Sr= |Y= |Zr= |Nb= |Mo= |Tc= |Ru= |Rh= |Pd= |Ag= |Cd= |In= |Sn= |Sb= |Te= |I= |Xe= |Cs= |Ba= |La= |Ce= |Pr= |Nd= |Pm= |Sm= |Eu= |Gd= |Tb= |Dy= |Ho= |Er= |Tm= |Yb= |Lu= |Hf= |Ta= |W= |Re= |Os= |Ir= |Pt= |Au= |Hg= |Tl= |Pb= |Bi= |Po= |At= |Rn= |Fr= |Ra= |Ac= |Th= |Pa= |U= |Np= |Pu= |Am= |Cm= |Bk= |Cf= |Es= |Fm= |Md= |No= |Lr= |Rf= |Db= |Sg= |Bh= |Hs= |Mt= |Ds= |Rg= |Uub= |Uut= |Lv= |Uup= |Fl= |Uus= |Uuo=
| round   =
| unit    =
| fixed   =
| ref     =
| comment =
| sortable=
| catname =
}}

Standard atomic weights used

Atomic number Z	Element	Molar mass g/mol	Note

0	C₉H₈O₄	7002180157000000000♠180.157	fixed value input
0	C₉H₈O₄	7002180157000000000♠180.157 g/mol	fixed value input
0	C₉H₈O₄	7002180159000000000♠180.159	aspirin
1	H	7000100800000000000♠1.008
2	He	7000400260200000000♠4.002602
3	Li	7000694000000000000♠6.94
4	Be	7000901218310000000♠9.0121831
5	B	7001108100000000000♠10.81
6	C	7001120110000000000♠12.011
7	N	7001140070000000000♠14.007
8	O	7001159990000000000♠15.999
9	F	7001189984031630000♠18.998403163
10	Ne	7001201797000000000♠20.1797
11	Na	7001229897692800000♠22.98976928
12	Mg	7001243050000000000♠24.305
13	Al	7001269815385000000♠26.9815385
14	Si	7001280850000000000♠28.085
15	P	7001309737619980000♠30.973761998
16	S	7001320600000000000♠32.06
17	Cl	7001354500000000000♠35.45
18	Ar	7001399480000000000♠39.948
19	K	7001390983000000000♠39.0983
20	Ca	7001400780000000000♠40.078
21	Sc	7001449559080000000♠44.955908
22	Ti	7001478670000000000♠47.867
23	V	7001509415000000000♠50.9415
24	Cr	7001519961000000000♠51.9961
25	Mn	7001549380440000000♠54.938044
26	Fe	7001558450000000000♠55.845
27	Co	7001589331940000000♠58.933194
28	Ni	7001586934000000000♠58.6934
29	Cu	7001635460000000000♠63.546
30	Zn	7001653790000000000♠65.38
31	Ga	7001697230000000000♠69.723
32	Ge	7001726300000000000♠72.63
33	As	7001749215950000000♠74.921595
34	Se	7001789710000000000♠78.971
35	Br	7001799040000000000♠79.904
36	Kr	7001837980000000000♠83.798
37	Rb	7001854678000000000♠85.4678
38	Sr	7001876200000000000♠87.62
39	Y	7001889058400000000♠88.90584
40	Zr	7001912240000000000♠91.224
41	Nb	7001929063700000000♠92.90637
42	Mo	7001959500000000000♠95.95
43	Tc	7001980000000000000♠98
44	Ru	7002101079999900000♠101.07
45	Rh	7002102905500000000♠102.9055
46	Pd	7002106420000000000♠106.42
47	Ag	7002107868200000000♠107.8682
48	Cd	7002112414000000000♠112.414
49	In	7002114818000000000♠114.818
50	Sn	7002118710000000000♠118.71
51	Sb	7002121760000000000♠121.76
52	Te	7002127600000000000♠127.6	(Does not follow atomic number)
53	I	7002126904470000000♠126.90447	(Does not follow atomic number)
54	Xe	7002131293000000000♠131.293
55	Cs	7002132905451960000♠132.90545196
56	Ba	7002137327000000000♠137.327
57	La	7002138905470000000♠138.90547
58	Ce	7002140116000000000♠140.116
59	Pr	7002140907660000000♠140.90766
60	Nd	7002144242000000000♠144.242
61	Pm	7002145000000000000♠145
62	Sm	7002150360000000000♠150.36
63	Eu	7002151964000000000♠151.964
64	Gd	7002157250000000000♠157.25
65	Tb	7002158925350000000♠158.92535
66	Dy	7002162500000000000♠162.5
67	Ho	7002164930330000000♠164.93033
68	Er	7002167258999900000♠167.259
69	Tm	7002168934220000000♠168.93422
70	Yb	7002173044999900000♠173.045
71	Lu	7002174966800000000♠174.9668
72	Hf	7002178490000000000♠178.49
73	Ta	7002180947880000000♠180.94788
74	W	7002183840000000000♠183.84
75	Re	7002186207000000000♠186.207
76	Os	7002190230000000000♠190.23
77	Ir	7002192217000000000♠192.217
78	Pt	7002195084000000000♠195.084
79	Au	7002196966569000000♠196.966569
80	Hg	7002200592000000000♠200.592
81	Tl	7002204380000000000♠204.38
82	Pb	7002207200000000000♠207.2
83	Bi	7002208980400000000♠208.9804
84	Po	7002209000000000000♠209
85	At	7002210000000000000♠210
86	Rn	7002222000000000000♠222
87	Fr	7002223000000000000♠223
88	Ra	7002226000000000000♠226
89	Ac	7002227000000000000♠227
90	Th	7002232037700000000♠232.0377
91	Pa	7002231035880000000♠231.03588
92	U	7002238028910000000♠238.02891
93	Np	7002237000000000000♠237
94	Pu	7002244000000000000♠244
95	Am	7002243000000000000♠243
96	Cm	7002247000000000000♠247
97	Bk	7002247000000000000♠247
98	Cf	7002251000000000000♠251
99	Es	7002252000000000000♠252
100	Fm	7002257000000000000♠257
101	Md	7002258000000000000♠258
102	No	7002259000000000000♠259
103	Lr	7002266000000000000♠266
104	Rf	7002267000000000000♠267
105	Db	7002268000000000000♠268
106	Sg	7002269000000000000♠269
107	Bh	7002270000000000000♠270
108	Hs	7002269000000000000♠269
109	Mt	7002278000000000000♠278
110	Ds	7002281000000000000♠281
111	Rg	7002281000000000000♠281
112	Cn	7002285000000000000♠285
113	Uut	7002286000000000000♠286
114	Fl	7002289000000000000♠289
115	Uup	7002289000000000000♠289
116	Lv	7002293000000000000♠293
117	Uus	7002294000000000000♠294
118	Uuo	7002294000000000000♠294

Data sources (CIAAW)

Primarily, the atomic weights used here are defined by CIAAW [1]:

"Standard Atomic Weights". Commission on Isotopic Abundances and Atomic Weights (CIAAW). 2015. http://www.ciaaw.org/atomic-weights.htm. Heintað 2015-09-20. (68 elements)
CIAAW also published additional lists in spreadsheet format (2013). It has additional conventional values for trade usage (12 elements), and some background information on the numbers and calculations.

Coplen, T.B.; Brand, W.A. (2013). "Atomic weights of the elements 2013 (xls)". CIAAW. http://www.ciaaw.org/publications.htm. Heintað 2015-05-26.

Some unstable elements can naturally occur, and so are listed (4 elements: Bi, Th, Pa, U)
Additional values are those of the most stable isotopes, as given in List of chemical elements (34 elements). This source is not supported by the CIAAW publications.

Embedding in a template

The template is designed to be embedded in a template like {{Drugbox}}. The molecular formula can be entered like ...|H=2|O=1, and these values then are passed through to this subtemplate, together with the other parameters like |round=.

For this usage one extra parameter is available:
|catname=. A category name entered here, which will be used as maintenance category for articles that have both calculated and fixed input. These are two inputs for one data value. The maintenance task is to remove the |fixed= input (unless overwriting is intentional).

Know issue: uncertainty

Atomic weights are given with a precision and uncertainty, for example: 20.1797(6) for neon (more here).

Uncertainty

This template does not maintain the uncertainty (the bracketed part). When done correctly, the uncertainty could influence the result, especially when precision (number of decimals) is larger.

Rounding

This template usually does rounding on the calculated result, to 2 decimals by default:

For neon: {{Chem molar mass|Ne=1}} → 20,18 g·mol⁻¹

Two decimals is common practice for trade and most laboratory situations. However, rounding is set to more decimals, and the compounnd has atoms with less precision, the resulting number will be inaccurate (suggesting a wrong precision). For example strontium :

{{Chem molar mass|Sr=1|round=4}} → 87,6200 g·mol⁻¹

Six elements have values ending with a final decimal being "0" (a zero), like Sn: 118.710. This value does not show for technical reasons (the calculation 'rounds them away'), but it does signify an extra precision. The six elements are Sn, Rh, Ge, Sb, Dy, Bi.

Calculate cumulative uncertainties

[2], [3]