قالب:Chem molar mass

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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 {{Infobox drug}} 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 H 2O) → 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<sup>−1</sup>|ref=<ref>Some source</ref>|comment=My Comment}} → 234.56 g·mol⁻¹^[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
<!-- with 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= |Cn= |Nh= |Lv= |Mc= |Fl= |Ts= |Og=
| round   =
| unit    =
| fixed   =
| ref     =
| comment =
| sortable=
| catname =
}}

Standard atomic weights used

Atomic number Z	Element	Molar mass g·mol⁻¹	Note

0	C 9H 8O 4	&0000000000000180157000180.157	fixed value input
0	C 9H 8O 4	&0000000000000180157000180.157 g·mol⁻¹	fixed value input
0	C 9H 8O 4	&0000000000000180158999180.159	aspirin
1	H	&00000000000000010080001.008
2	He	&00000000000000040026024.002602
3	Li	&00000000000000069400006.94
4	Be	&00000000000000090121839.0121831
5	B	&000000000000001081000010.81
6	C	&000000000000001201099912.011
7	N	&000000000000001400699914.007
8	O	&000000000000001599900015.999
9	F	&000000000000001899840318.998403163
10	Ne	&000000000000002017970020.1797
11	Na	&000000000000002298976922.98976928
12	Mg	&000000000000002430499924.305
13	Al	&000000000000002698153826.9815385
14	Si	&000000000000002808500028.085
15	P	&000000000000003097376130.973761998
16	S	&000000000000003206000032.06
17	Cl	&000000000000003545000035.45
18	Ar	&000000000000003994800039.948
19	K	&000000000000003909830039.0983
20	Ca	&000000000000004007800040.078
21	Sc	&000000000000004495590844.955908
22	Ti	&000000000000004786699947.867
23	V	&000000000000005094149950.9415
24	Cr	&000000000000005199609951.9961
25	Mn	&000000000000005493804354.938044
26	Fe	&000000000000005584499955.845
27	Co	&000000000000005893319458.933194
28	Ni	&000000000000005869339958.6934
29	Cu	&000000000000006354599963.546
30	Zn	&000000000000006537999965.38
31	Ga	&000000000000006972299969.723
32	Ge	&000000000000007262999972.63
33	As	&000000000000007492159474.921595
34	Se	&000000000000007897100078.971
35	Br	&000000000000007990399979.904
36	Kr	&000000000000008379800083.798
37	Rb	&000000000000008546779985.4678
38	Sr	&000000000000008762000087.62
39	Y	&000000000000008890583988.90584
40	Zr	&000000000000009122400091.224
41	Nb	&000000000000009290636992.90637
42	Mo	&000000000000009595000095.95
43	Tc	&000000000000009800000098
44	Ru	&0000000000000101069999101.07
45	Rh	&0000000000000102905500102.9055
46	Pd	&0000000000000106420000106.42
47	Ag	&0000000000000107868200107.8682
48	Cd	&0000000000000112414000112.414
49	In	&0000000000000114817999114.818
50	Sn	&0000000000000118709999118.71
51	Sb	&0000000000000121760000121.76
52	Te	&0000000000000127599999127.6	(Does not follow atomic number)
53	I	&0000000000000126904470126.90447	(Does not follow atomic number)
54	Xe	&0000000000000131293000131.293
55	Cs	&0000000000000132905451132.90545196
56	Ba	&0000000000000137326999137.327
57	La	&0000000000000138905470138.90547
58	Ce	&0000000000000140116000140.116
59	Pr	&0000000000000140907659140.90766
60	Nd	&0000000000000144241999144.242
61	Pm	&0000000000000145000000145
62	Sm	&0000000000000150360000150.36
63	Eu	&0000000000000151963999151.964
64	Gd	&0000000000000157250000157.25
65	Tb	&0000000000000158925350158.92535
66	Dy	&0000000000000162500000162.5
67	Ho	&0000000000000164930329164.93033
68	Er	&0000000000000167258999167.259
69	Tm	&0000000000000168934220168.93422
70	Yb	&0000000000000173044999173.045
71	Lu	&0000000000000174966800174.9668
72	Hf	&0000000000000178490000178.49
73	Ta	&0000000000000180947879180.94788
74	W	&0000000000000183840000183.84
75	Re	&0000000000000186206999186.207
76	Os	&0000000000000190229999190.23
77	Ir	&0000000000000192217000192.217
78	Pt	&0000000000000195084000195.084
79	Au	&0000000000000196966568196.966569
80	Hg	&0000000000000200592000200.592
81	Tl	&0000000000000204379999204.38
82	Pb	&0000000000000207199999207.2
83	Bi	&0000000000000208980400208.9804
84	Po	&0000000000000209000000209
85	At	&0000000000000210000000210
86	Rn	&0000000000000222000000222
87	Fr	&0000000000000223000000223
88	Ra	&0000000000000226000000226
89	Ac	&0000000000000227000000227
90	Th	&0000000000000232037700232.0377
91	Pa	&0000000000000231035879231.03588
92	U	&0000000000000238028909238.02891
93	Np	&0000000000000237000000237
94	Pu	&0000000000000244000000244
95	Am	&0000000000000243000000243
96	Cm	&0000000000000247000000247
97	Bk	&0000000000000247000000247
98	Cf	&0000000000000251000000251
99	Es	&0000000000000252000000252
100	Fm	&0000000000000257000000257
101	Md	&0000000000000258000000258
102	No	&0000000000000259000000259
103	Lr	&0000000000000266000000266
104	Rf	&0000000000000267000000267
105	Db	&0000000000000268000000268
106	Sg	&0000000000000269000000269
107	Bh	&0000000000000270000000270
108	Hs	&0000000000000269000000269
109	Mt	&0000000000000278000000278
110	Ds	&0000000000000281000000281
111	Rg	&0000000000000281000000281
112	Cn	&0000000000000285000000285
113	Nh	&0000000000000286000000286
114	Fl	&0000000000000289000000289
115	Mc	&0000000000000289000000289
116	Lv	&0000000000000293000000293
117	Ts	&0000000000000294000000294
118	Og	&0000000000000294000000294

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. Retrieved 2015-09-20. (68 elements)
CIAAW also published additional lists in spreadsheet format (2013). It has additional conventional values for trade usage, and some background information on the numbers and calculations. (12 elements: B, Br, C, Cl, H, Li, Mg, N, O, S, Si, Tl).

Coplen, T.B.; Brand, W.A. (2013). "Atomic weights of the elements 2013 (xls)". CIAAW. Retrieved 2015-05-26. {{cite web}}: Unknown parameter |displayauthors= ignored (|display-authors= suggested) (help)

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.

See also: "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. February 2016. pp. 265–291. doi:10.1515/pac-2015-0305. eISSN 1365-3075. ISSN 0033-4545. Retrieved 2016-12-29.

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]