Knowledge (XXG)

Talk:Molar mass

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molecular mass because they are commonly nearly identical numerically. For many common chemicals the most abundant isotopomer will be very close to the isotopic average and using them interchangably will often not have disastrous results and thus such misuse is perpetuated. I personally never ever do this because I measure molecular masses down to several decimal places every day. I am a top candidate for zealtory on this issue but try to moderate and explain. I thank you for the recent improvements they improve the clarity and accuracy. Your work is excellent.--
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6.02X10^23 copies of a subtance. For example, the molar mass of 6 X 10^23 atoms of carbon 12 is defined as exctly 12;....] then get more complex as a PhD, I know how hard simplifying things is; the intro sucks (sorry..) howerver, i no longer contribute to wik because *for profits* can re use my work I don't mind if a nonprofit takes what I have done, but I will be dam**ed if I will work for free so some rich scum sucking 1% can get even richer off of my work
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the problem. While we are discussing things I do not see the need to discuss kg/mol in the context of the molar mass versus molecular mass section. I fully understand the need to discuss it in general. It is discussed directly above in the introductory section. If we stick to g/mol within this section for the sake of simplicity of addressing the issue at hand without saying that it must be this or that everything is simpler and clearer. e.g.
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managed a rather lacklustre grade C. What I do remember is that a "mole" was never described in any useful context, it appeared one day and we were apparently just expected to accept that it was a thing. I can accept it is a thing, but in order to understand the things that reference it, something a little more specific might be useful! --
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While NickY's sentence is clear and brief, unfortunately it is also incorrect. the numerical value of the relative molecular mass and the numerical value of the molar mass can vary by several units. The molar mass of natural water is 18.0152 g/mol, the molecular mass of natural water falls between 18
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17:06, 5 January 2007 (UTC) as a scientist who has to use Molar concentrations all day long, I think the intro is impossibly confused and complex. It should be something simple like, molar mass is the mass (weight) of one mole of a substance; a mole is 6.02 X 10^23, so the molar mass is the weight of
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The molecular weight of sugar is 342 and that means there are 342 grams per mole. Its that simple! Why confuse things so tremendously by introducing the obscure Dalton unit and molar mass versus molecular mass?? Knowledge (XXG) isn't meant to be read only by PhD physicists and chemists ... it is also
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Molar mass is the mass of one mole of a chemical element or chemical compound. In SI, the unit is kg/mol. The molar mass can be obtained from the relative molecular mass (still often called erroneously molecular weight and abbreviated by MW) multiplying it by 0.001 kg/mol. there is no element called
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I have been working slowly on these related articles. They were in horrible shape before I got to them. They said things such as the molecular mass is the same as the molar mass but with different units. I certainly think there is much room for improvement and welcome your working on them. Probably
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to use the same units. I.e. that the molar mass of water could be described as 108.396x10 u. Conversely molecular mass may be expressed as some very small number in g/mol. There is no reason to do such a thing but the units do not differ by definition and the insertion of a single word gets around
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One what? I've scanned the article and some of the links and I've no idea what "one mole of that substance" might be. A kg? A cup? A swimming-pool? I have no idea. I'm not being deliberately obtuse, and vaguely remember the term "mole" being used when I studied O-level chemistry, in which I
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Your last sentence is clear and brief. BTW the reason for speaking about kg/mol is that this is an SI unit (not kg/kmol as I thought for a long time). But I too have the habit of ignoring SI, and speak for instance freely in kcal/mol, because I remember those values best. So it is OK by me if we
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I agree completely with you Physchim. My statement is only correct when considering the most abundant isotopers of most elements. The point I was making was that it is common for lay people or even scientists not directly involved in such issues on a regular basis to confuse the molar mass and
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I agree completely. I have changed the sentence in question. I believe that the odd phrasing of the question was born of of SI unit zealotry and OR through synthesis. kg is base unit of mass therefore kg/mol is base unit of molar mass. Not true. I am glad to have some good editors helping out
249:. Both masses could be expressed in the same units (say kg), but then of course the numeric values would be different by a factor on the order of 10. I understand that you know all of this, but for clarity we should be careful about the formulation of these things.-- 841:
redirects here, but isn't discussed here. Specifically, it is important for things that aren't molecular, such as ionic crystals. A standard formula is given, which gives the relative numbers of atoms, even without molecular units.
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you can find some places where I was not bold enough and too compromising to misnomers. I do think it is important to recognize that it is common practice even amongst chemists to use these terms interchangeably (incorrectly). --
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Would it be possible to add a few examples for compound calculations? Can be simple, and few examples but just as a quick explanation so that people can check that they did calculate the right values on their own.
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and 22 amu (not counting tritium isotopers). When you are talking about molecular mass, you simply cannot take only the most abundant isotopomer: it might be simpler, but it's just as simply wrong.
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as a method of determining molar mass, and may be expand a little more on the question of polymers (not my speciality, but I can try...) The related articles also need to be looked at, especially
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The fact is that u, Da, g/mol, kg/mol are all used by physicists, protein mass spectrometrists, chemists, and SI-ists respectively. Tangled yes but we can't really sweep it under the rug. --
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I'm not sure the emphasis in "kg/mol being the SI unit" is needed, but what worries me the most is that a reader might get the idea that g/mol is not SI. The kilogram may be the
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of the atoms which form the compound multiplied by the molar mass constant" - do we change from atomic mass to atomic weights when considering compounds rather than elements?
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I agree with you for the most part. The issue that I was trying to avoid, which is an idiotic one in my opinion, is that there really is no restriction on units and it is
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Agreed completely. Atomic masses have relatively little to do with the Molar Mass of an element and definitely not with the relation suggested. The key here is
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No, a gram atom is exactly the same as a mole of atoms of an element. You can always have a mole of atoms, whether the elements is monatomic or not.
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In the section describing common Molar masses, parenthesis are used in an uncommon (at least to the layman) manner, resulting in confusion.
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Does the (7) above mean multiplication by 7? Does it mean multiplication by 7th power of 10? Does it mean something else entirely? -
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I'm glad you like them, obviously, and I'm flattered. I still have one or two things I would like to do here, such as a discussion of
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saying "The SI unit for intercity distance is the meter. However, for historical reasons the kilometer is more commonly used". :-) --
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for molecular mass. For most compounds (when using g/mol and u) the numeric values are not exactly equal but differ slightly."
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At present we have the definition for an element as "The molar mass of atoms of an element is given by the standard
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Msg. to Nick Y: molar mass is the macroscopic mass of roughly 10 molecules, whereas molecular mass is the mass of
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of the element multiplied by the molar mass constant". This seems to me to be incorrect for a number of reasons.
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can someone explain what the 97(7) thing is for dummies? and why the following line is different, only has (5)
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molecule. So, they differ in their units when their numeric values are (almost) equal, which is why I deleted
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The definition for a compound is given as "The molar mass of a compound is given by the sum of the standard
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Mass of a mole is called molar mass we can obtained it by molecular mass by miltiplying it by 0.001kg/mol.
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on Knowledge (XXG). If you would like to participate, please visit the project page, where you can join
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I'd suggest that the definition for an element ought to use the atomic weight - does anyone agree? --
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The dimensions are wrong, since atomic mass is in mass units and the constant has units of mass/mole;
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are approximately equal, although they differ in their units, namely g/mol (chemistry) or kg/mol (
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redirects here but this is misleading. A Gram atom is only the same as a mole in the case of
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unit, but gram is certainly also SI! An analogous example would be to have an article on
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Is molar mass and molarity is same? What are the symbols used for both.
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the dalton is there, it is just a unit of measurement isn't it?
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The reference used to support the definition for an element is
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simply use g/mol. Will you make the changes? Thank you, --
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Should 891:08:42, 25 December 2021 (UTC) 786:21:36, 16 December 2018 (UTC) 93:and see a list of open tasks. 792:"one mole of that substance" 715:20:25, 2 December 2018 (UTC) 651:Notation needs clarification 556:Atomic mass or atomic weight 548:21:35, 7 February 2010 (UTC) 536:17:17, 7 February 2010 (UTC) 517:16:57, 7 February 2010 (UTC) 490:16:18, 20 January 2009 (UTC) 470:22:30, 19 January 2009 (UTC) 438:17:02, 17 October 2007 (UTC) 427:10:47, 17 October 2007 (UTC) 402:17:14, 17 October 2007 (UTC) 389:12:58, 17 October 2007 (UTC) 354:19:23, 16 October 2007 (UTC) 334:13:02, 13 October 2007 (UTC) 693:17:16, 13 August 2018 (UTC) 237:molar versus molecular mass 960: 934:C-Class Chemistry articles 904:point here or redirect to 590:Pure and Applied Chemistry 182:20:50, 25 April 2006 (UTC) 125:project's importance scale 920:05:03, 18 June 2024 (UTC) 896:Molecular weight redirect 872:12:04, 19 July 2021 (UTC) 852:18:05, 21 June 2019 (UTC) 776:What a bad performance. - 643:17:53, 18 June 2010 (UTC) 231:20:31, 22 June 2012 (UTC) 118: 67: 46: 622:12:33, 28 May 2010 (UTC) 317:19:01, 11 May 2007 (UTC) 301:18:15, 11 May 2007 (UTC) 254:11:36, 11 May 2007 (UTC) 163:07:35, 5 June 2008 (UTC) 826:12:53, 6 May 2019 (UTC) 807:12:29, 6 May 2019 (UTC) 701:Molar mass and molarity 604:10.1351/pac200678112051 478:Measurement uncertainty 631:Standard Atomic Weight 580:Wieser, M. E. (2006), 444:regarding the examples 28:This article is rated 205:) 12:24, 20 July 2006 82:WikiProject Chemistry 32:on Knowledge (XXG)'s 707:Rupendra singh maura 522:I have restored the 881:What is molar mass 816:into a link now.-- 420:intercity distance 105:Chemistry articles 34:content assessment 770: 769: 460:comment added by 221:comment added by 207: 193:comment added by 165: 153:comment added by 139: 138: 135: 134: 131: 130: 951: 915: 902:Molecular weight 731: 728:, showing this: 607: 606: 586: 524:Gram atomic mass 501:Gram atomic mass 496:Gram atomic mass 472: 410:Regarding kg/mol 286:Could be simply: 233: 206: 187: 148: 107: 106: 103: 100: 97: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 959: 958: 954: 953: 952: 950: 949: 948: 924: 923: 909: 898: 879: 859: 836: 794: 763: 741: 722: 703: 653: 597:(11): 2051–66, 584: 579: 558: 498: 462:124.176.100.173 455: 446: 412: 239: 216: 188: 174: 144: 121:High-importance 104: 101: 98: 95: 94: 62:High‑importance 61: 29: 12: 11: 5: 957: 955: 947: 946: 941: 936: 926: 925: 912:TARDIS builder 906:Molecular mass 897: 894: 883:110.37.200.117 878: 875: 858: 855: 839:formula weight 835: 833:formula weight 830: 829: 828: 812:I have turned 793: 790: 789: 788: 772: 768: 767: 764: 761: 758: 757: 754: 748: 747: 742: 740:Common symbols 739: 736: 735: 721: 718: 702: 699: 698: 697: 696: 695: 664: 663: 652: 649: 648: 647: 646: 645: 610: 609: 576: 573:atomic weights 569: 557: 554: 553: 552: 551: 550: 497: 494: 493: 492: 445: 442: 441: 440: 411: 408: 407: 406: 405: 404: 371:molecular mass 363: 362: 361: 360: 359: 358: 357: 356: 339: 338: 337: 336: 322: 321: 320: 319: 304: 303: 293: 292: 288: 287: 283: 282: 271:molecular mass 266: 265: 238: 235: 195:59.144.134.240 173: 170: 168: 143: 140: 137: 136: 133: 132: 129: 128: 117: 111: 110: 108: 91:the discussion 77: 65: 64: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 956: 945: 942: 940: 937: 935: 932: 931: 929: 922: 921: 918: 914: 913: 907: 903: 895: 893: 892: 888: 884: 876: 874: 873: 869: 865: 856: 854: 853: 849: 845: 840: 834: 831: 827: 823: 819: 815: 811: 810: 809: 808: 804: 800: 791: 787: 783: 779: 775: 774: 773: 765: 759: 755: 753: 749: 746: 743: 737: 732: 729: 727: 719: 717: 716: 712: 708: 700: 694: 690: 686: 682: 679: 678: 677: 676: 675: 673: 669: 661: 658: 657: 656: 650: 644: 640: 636: 632: 628: 627: 626: 625: 624: 623: 619: 615: 605: 600: 596: 592: 591: 583: 577: 574: 570: 567: 566: 565: 563: 555: 549: 546: 543: 539: 538: 537: 533: 529: 525: 521: 520: 519: 518: 514: 510: 506: 502: 495: 491: 487: 483: 479: 475: 474: 473: 471: 467: 463: 459: 452: 449: 443: 439: 436: 431: 430: 429: 428: 425: 421: 417: 409: 403: 400: 395: 394: 393: 392: 391: 390: 387: 384: 380: 376: 375:atomic weight 372: 368: 355: 352: 347: 346: 345: 344: 343: 342: 341: 340: 335: 332: 329: 324: 323: 318: 315: 310: 309: 308: 307: 306: 305: 302: 299: 295: 294: 290: 289: 285: 284: 280: 276: 272: 268: 267: 262: 258: 257: 256: 255: 252: 248: 244: 236: 234: 232: 228: 224: 223:68.236.121.54 220: 213: 208: 204: 200: 196: 192: 184: 183: 180: 171: 169: 166: 164: 160: 156: 155:124.182.147.2 152: 141: 126: 122: 116: 113: 112: 109: 92: 88: 84: 83: 78: 75: 71: 70: 66: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 910: 899: 880: 860: 837: 795: 771: 744: 723: 704: 668:JoeOfTheWiki 665: 659: 654: 630: 611: 594: 588: 572: 561: 559: 499: 453: 450: 447: 415: 413: 364: 260: 246: 242: 240: 217:— Preceding 209: 185: 175: 167: 145: 120: 80: 40:WikiProjects 762:Other units 724:I just saw 562:atomic mass 456:—Preceding 379:atomic mass 212:Rifleman 82 189:—Preceding 149:—Preceding 928:Categories 818:RolfSander 734:Molar mass 726:molar mass 685:RolfSander 542:Physchim62 528:Biscuittin 509:Biscuittin 507:elements. 454:Thankyou 383:Physchim62 328:Physchim62 142:molar mass 877:Chemistry 526:article. 505:monatomic 367:osmometry 96:Chemistry 87:chemistry 59:Chemistry 857:Examples 458:unsigned 314:P.wormer 261:possible 251:P.wormer 219:unsigned 203:contribs 191:unsigned 179:mbeychok 151:unsigned 799:Vometia 752:SI unit 635:Nick Y. 482:Nick Y. 435:Nick Y. 433:here.-- 399:Nick Y. 351:Nick Y. 298:Nick Y. 247:usually 123:on the 30:C-class 908:?   — 778:DePiep 756:kg/mol 545:(talk) 386:(talk) 331:(talk) 36:scale. 766:g/mol 614:RexxS 585:(PDF) 887:talk 868:talk 848:talk 844:Gah4 822:talk 814:mole 803:talk 782:talk 711:talk 689:talk 672:talk 639:talk 633:. -- 618:talk 532:talk 513:talk 486:talk 466:talk 424:Itub 416:base 377:and 227:talk 199:talk 159:talk 115:High 599:doi 480:.-- 243:one 930:: 889:) 870:) 850:) 824:) 805:) 784:) 713:) 691:) 683:-- 674:) 641:) 620:) 595:78 593:, 587:, 534:) 515:) 488:) 468:) 373:, 296:-- 275:SI 229:) 201:• 161:) 917:★ 885:( 866:( 846:( 820:( 801:( 780:( 745:M 709:( 687:( 670:( 660:M 637:( 616:( 601:: 530:( 511:( 484:( 464:( 279:u 225:( 197:( 157:( 127:. 42::

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content assessment
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Chemistry
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WikiProject Chemistry
chemistry
the discussion
High
project's importance scale
unsigned
124.182.147.2
talk
07:35, 5 June 2008 (UTC)
mbeychok
20:50, 25 April 2006 (UTC)
unsigned
59.144.134.240
talk
contribs
Rifleman 82
unsigned
68.236.121.54
talk
20:31, 22 June 2012 (UTC)
P.wormer
11:36, 11 May 2007 (UTC)
molecular mass
SI

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