This
level-3 vital article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||
|
This article was selected as the article for improvement on 22 February 2016 for a period of one week. |
The contents of the Molecular structure page were merged into Molecule on 29 June 2013. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
|
|
In the introductory paragraph, aggregate (a total considered with reference to its constituent parts) seems quite a bit more suitable than collection (an accumulation; a deposit) or even collective (this last one was masked vandalism).
As for the diamond "molecule": the term molecule refers to a well-defined particle of a chemically pure substance. Atomically pure diamond yields no well-defined molecular particle anyone could point to. Moreover, a common diamond crystal will always carry lattice and surface defects that make its local chemical properties different than the bulk. Even the most perfect diamond crystal will have surface terminal groups (hydrogens, hydroxyls, carbonyls, etc.) and so it will not be a pure chemical substance overall. It will be a covalent structure, though.
-- Unconcerned 07:08, 13 September 2006 (UTC)
I have been reverted by User:Vsmith (reason: per ref Zumdahl). Thus, I am putting the topic here to discuss further. The intro definition as it stands is:
Not all molecules are held together by covalent bonds, an example being DNA which is held together by hydrogen bonds. Moreover, most supermolecules are held together by non-covalent bonds. It would be correct to say that:
This would be all inclusive. -- Sadi Carnot 17:33, 17 September 2006 (UTC)
Vsmith, you are very inflexible and you argue in a way that contradicts yourself. Specifically, I was the one who originally provided a definition based on a widely used text reference (see: April 24, 2006 ):
It was you who modified that definition so to make the situation problematic. You state that your widely used 4th edition text supposedly replaced my 6th edition text. Sounds backward to me? -- Sadi Carnot 16:03, 18 September 2006 (UTC)
Moreover, here are more “textbook” definitions:
I hope these definitions clarify my point; I will now change the definition accordingly per these defintions and the above vote. -- Sadi Carnot 16:33, 18 September 2006 (UTC)
Where is this vote? This is a supposed discussion, not a vote. Inflexible? Simply said start simple and then expand the definition to cover variables introduced by biomolecules, polymers and supermolecules. Covalent bonds are the most prevalent bonds within molecules - especially simple species such as water, methane, ammonia, etc. The additional text defs provided do indicate a lack of rigor among text writers - the definitions are quite vague and could include almost anything. And that held together by special forces bit makes it sound like a military thing -- leastwise that's the image that special forces pops into my head. Cheers, Vsmith 00:32, 19 September 2006 (UTC)
So, is sodium chloride composed of molecules? How about silica or diamond? Or graphite? And how about a protein, DNA? How about acetic acid dimers in gas phase? If you ask me, the answers would be no, no, no, no, yes, two different, two identical. Chemical bonds seem a bit loose for a definition. Does it include ionic bonds? -- Rifleman 82 11:54, 6 November 2006 (UTC)
Encyclopedia Britannica defines a molecule as: "the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance." The definition paragraph says this breaks down but offers no citation. Reading this discussion I see that various chemistry encyclopedia's offer different definitions but none seem to refute the Britannica definition. We should keep in mind that wikipedia should be accessible to the largest audience possible and not just to specialists. Please review the copy of the Encyclopedia Britannica article at:
If there is no comment regarding my discussion post within a reasonable amount of time I will be inclined to change the first paragraph to match the Britannica definition.
sabbetius 19:37, 27 May 2007 (UTC)Sabbetius
Moved to: Talk:History of the molecule
Despite the fact that the overwhelmingly vast majority of molecules are composed of greater than one atom this is not a requirement! The definition of a molecule is the smallest component of a pure compound that retains all properties of the compound. This is a practical definition. A pure compound is composed of only one kind of molecule. This is what scientists understood before they understood the concept that bonding. Of course noble gases are molecules despite the fact that the are monoatomic! If you use this definition then the questions that are being posed can be answered by the definition instead of intuition. If you don't believe me then try to stump me. M stone 00:38, 1 May 2007 (UTC)
My opinion is that the most sensible definition of molecule should include monatomic entities such as noble gases. Unfortunately, all the commonly accepted definitions, including IUPAC's, require that molecules have at least two atoms. So that's what we must report in Wikipedia. -- Itub 20:13, 6 May 2007 (UTC)
Cacycle, you have just reverted the introductory section of that article to a vulnerable state that in the past had justified a long series of wild edits and contributions. The version you have modified was the result of a cooperative effort of capturing the essence of various definitions and aspects, and --rather than being stale-- it was relatively stable for a long period of time because of the achieved consensus. Please take a look at the history and the discussion page.
The IUPAC definition by itself is not sufficient for the broader scope of this article as it is given from the narrow perspective of theoretical chemistry. The multiple citations referenced by user:Sadi_Carnot as note 1 are proof of the wide inconsistence in defining a molecule among authoritative academia circles.
In science, a molecule is a sufficiently stable electrically neutral group of at least two atoms in a definite arrangement held together by strong chemical bondss. Only in the kinetic theory of gaseses the term molecule is often used for any gaseous particle regardless of their composition.
Also, the short discussion about divisibility that you have wiped was provided in support of that most general definition involving the "smallest particle..." and is of historical importance (see for ex. here as well as history of the molecule)
Molecules and atoms are the smallest particles of pure chemical substances that still retain their composition and chemical properties.
Also, it is incorrect to include NaCl in the discussion about network solids. That discussion was intended to differentiate the concepts of covalent vs. molecular.
No typical molecule can be defined for ionic ( salts) and covalent crystals ( network solids) which are composed of repeating unit cells that extend either in a plane (such as in graphite) or three-dimensionally (such as in diamond or sodium chloride).
I guess the general message here is that most things were included in the article for a reason, and hope you will reconsider your next edit, but for now I am revering to the mentioned version and would appreciate your discussing the intended contribution on the talk page-- Unconcerned 03:10, 1 May 2007 (UTC)
I think that the statement "The smallest molecular species that has a bond is the hydrogen ion molecule H2+, comprised of two protons bonded together by the sharing of one electron" is incorrect. I would assume that removing an electron would increase the bond length and thus H2+ would be larger in size than to nuetral H2. H2+ is the molecule with the least number of total electrons, however I am not sure why this is important. I think that this statement needs to be corrected or referenced. M stone 06:06, 25 May 2007 (UTC)
Something needs to be added to define molecular species, particularly molecular ions such as H2+ and common ions like sulfate. I'm not sure where though. Any ideas? -- Bduke 09:18, 8 June 2007 (UTC)
I thought that consensus was reached on H2+. It is confusing to talk about size in terms of the number of particles. H2 is the smallest molecule because it has the shortest bond length. H2+ is the simplest molecule because it is composed of the fewest number of particles. However, H2+ is larger than H2. I have changed things back to previous consensus. would appriciate if a bond length were found for H2+ before it was readded. M stone 19:35, 1 October 2007 (UTC)
I'm not sure I understand what Molecular compound is trying to say. I think it is meaning molecules and so anything new should be here. It apparently is to contrast with Ionic compound; but, I don't believe molecular compound is a common usage. ChemGardener 02:54, 22 June 2007 (UTC)
Moved to Talk:Human molecule. -- Sadi Carnot 14:30, 28 September 2007 (UTC)
In Molecular biology the "small molecule" name applies to organic molecule that are not biopolymers and that are not biologically inert (they are small as a consequence of not being a polymer). it redirects here, which is not good. So I will make an article and see what I can conjure up. Help very welcome. -- Squidonius ( talk) 23:47, 5 May 2008 (UTC)
I know a few elements that combine with others to form a molecule, like:
What other atoms/elements are there? Please awnser Androo123 ( talk) 19:45, 20 June 2008 (UTC)
I think that external links are all spam. I just noticed based on the most recent addition. I think they should all be erased. M stone ( talk) 10:56, 28 June 2008 (UTC)
"... a molecule is defined as a sufficiently stable, electrically neutral group..."
"The simplest of molecules is the hydrogen molecule-ion, H2+ ..."
P99am ( talk) 09:30, 24 April 2009 (UTC)
I think that the main problem is not in the hydrogen ion, but in the definition. It may be better to say:
Not "is defined".-- P99am ( talk) 12:57, 24 April 2009 (UTC)
Your definition is much better than given in this article. Nevertheless, it does not make clarity. And no one definition of the molecule create clarity. And it's good. We need explanations, not definitions.-- P99am ( talk) 15:24, 29 April 2009 (UTC)
molecules —Preceding unsigned comment added by 75.74.111.30 ( talk) 21:51, 26 August 2009 (UTC)
Can this image be added to this article? That is the best image of a molecule in existence. 85.65.69.166 ( talk) 03:15, 1 September 2009 (UTC)
image show now ¢$₯₣ — Preceding unsigned comment added by 39.32.88.30 ( talk) 17:57, 22 October 2013 (UTC)
i believe that an article about molecules should show at least 3-5 photos of molecules from microscopes... — Preceding unsigned comment added by 79.182.15.64 ( talk) 10:39, 19 September 2011 (UTC)
The text under this image is faulty. It states that the middle and left images are 3d, and that the right one is 2d. The problem is that the right one also is (partially) 3d. As you guys know the way the bonds are displayed gives information about the invisible z-axis. It's not very obvious and more of a wrong nuance, but I do think something should be changed.
Potential solutions are, change the text and change the image.
The information given by the text is valid and relevant, so I think it is preferable to change the image.
What do you guys think?
Bartiosos (
talk) 08:25, 12 February 2014 (UTC)
Ionic bonds: Molecules with ionic bonds are quite uncommonly encountered, sure gaseous sodium fluoride may be ionic and a molecule, but any liquids or solids that use ionic bonds will form networks, and not be molecular.
Target audience: Our target audience may be grade 6 or 7 students, so some of the more technical stuff needs more explaining. Perhaps we need more comparisons for scaling. Perhaps we need to give numbers of molecules (mols).
Referencing is poor, likely because our writers know this stuff, and do not neeed to look at a text book.
Categories of molecules.
Shapes of molecules (include symmetries)
properties as a gas.
Properties when condensed, liquids and solids
Graeme Bartlett ( talk) 10:13, 29 February 2016 (UTC)
I think that the statement in the article that organic chemists include polyatomic ions in the definition of "molecule" is, clearly, not supported, according to my experience in organic chemistry for 50 years. If this definition is found in one or two sources, it certainly should be considered an "outlier" ` Frankxxxx ( talk) 03:00, 26 November 2021 (UTC)
molecule is made up of more than one atom Balabharathi.v ( talk) 14:06, 2 December 2021 (UTC)
I have removed some irrelevnt info from lists of molecules i shall copy it here in case someone wants to incirpartate into this article:
Amedeo Avogadro created the word "molecule". [1] His 1811 paper "Essay on Determining the Relative Masses of the Elementary Molecules of Bodies" states, according to Partington's A Short History of Chemistry, that: [2]
The smallest particles of gases are not necessarily simple atoms, but are made up of a certain number of these atoms united by attraction to form a single molecule.
References
If two or more than two atoms combine to form molecule Then how is He Ne molecule as they are monoatomic and no atoms are combined??? The right definition of molecule is the smallest particles of matter which can exist independently as separate unit Asadalimukhlis ( talk) 03:47, 20 May 2023 (UTC)
This article is currently the subject of a Wiki Education Foundation-supported course assignment, between 12 February 2024 and 14 June 2024. Further details are available on the course page. Student editor(s): GiaTran21 ( article contribs).
— Assignment last updated by GiaTran21 ( talk) 23:22, 11 March 2024 (UTC)
This
level-3 vital article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||
|
This article was selected as the article for improvement on 22 February 2016 for a period of one week. |
The contents of the Molecular structure page were merged into Molecule on 29 June 2013. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
|
|
In the introductory paragraph, aggregate (a total considered with reference to its constituent parts) seems quite a bit more suitable than collection (an accumulation; a deposit) or even collective (this last one was masked vandalism).
As for the diamond "molecule": the term molecule refers to a well-defined particle of a chemically pure substance. Atomically pure diamond yields no well-defined molecular particle anyone could point to. Moreover, a common diamond crystal will always carry lattice and surface defects that make its local chemical properties different than the bulk. Even the most perfect diamond crystal will have surface terminal groups (hydrogens, hydroxyls, carbonyls, etc.) and so it will not be a pure chemical substance overall. It will be a covalent structure, though.
-- Unconcerned 07:08, 13 September 2006 (UTC)
I have been reverted by User:Vsmith (reason: per ref Zumdahl). Thus, I am putting the topic here to discuss further. The intro definition as it stands is:
Not all molecules are held together by covalent bonds, an example being DNA which is held together by hydrogen bonds. Moreover, most supermolecules are held together by non-covalent bonds. It would be correct to say that:
This would be all inclusive. -- Sadi Carnot 17:33, 17 September 2006 (UTC)
Vsmith, you are very inflexible and you argue in a way that contradicts yourself. Specifically, I was the one who originally provided a definition based on a widely used text reference (see: April 24, 2006 ):
It was you who modified that definition so to make the situation problematic. You state that your widely used 4th edition text supposedly replaced my 6th edition text. Sounds backward to me? -- Sadi Carnot 16:03, 18 September 2006 (UTC)
Moreover, here are more “textbook” definitions:
I hope these definitions clarify my point; I will now change the definition accordingly per these defintions and the above vote. -- Sadi Carnot 16:33, 18 September 2006 (UTC)
Where is this vote? This is a supposed discussion, not a vote. Inflexible? Simply said start simple and then expand the definition to cover variables introduced by biomolecules, polymers and supermolecules. Covalent bonds are the most prevalent bonds within molecules - especially simple species such as water, methane, ammonia, etc. The additional text defs provided do indicate a lack of rigor among text writers - the definitions are quite vague and could include almost anything. And that held together by special forces bit makes it sound like a military thing -- leastwise that's the image that special forces pops into my head. Cheers, Vsmith 00:32, 19 September 2006 (UTC)
So, is sodium chloride composed of molecules? How about silica or diamond? Or graphite? And how about a protein, DNA? How about acetic acid dimers in gas phase? If you ask me, the answers would be no, no, no, no, yes, two different, two identical. Chemical bonds seem a bit loose for a definition. Does it include ionic bonds? -- Rifleman 82 11:54, 6 November 2006 (UTC)
Encyclopedia Britannica defines a molecule as: "the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance." The definition paragraph says this breaks down but offers no citation. Reading this discussion I see that various chemistry encyclopedia's offer different definitions but none seem to refute the Britannica definition. We should keep in mind that wikipedia should be accessible to the largest audience possible and not just to specialists. Please review the copy of the Encyclopedia Britannica article at:
If there is no comment regarding my discussion post within a reasonable amount of time I will be inclined to change the first paragraph to match the Britannica definition.
sabbetius 19:37, 27 May 2007 (UTC)Sabbetius
Moved to: Talk:History of the molecule
Despite the fact that the overwhelmingly vast majority of molecules are composed of greater than one atom this is not a requirement! The definition of a molecule is the smallest component of a pure compound that retains all properties of the compound. This is a practical definition. A pure compound is composed of only one kind of molecule. This is what scientists understood before they understood the concept that bonding. Of course noble gases are molecules despite the fact that the are monoatomic! If you use this definition then the questions that are being posed can be answered by the definition instead of intuition. If you don't believe me then try to stump me. M stone 00:38, 1 May 2007 (UTC)
My opinion is that the most sensible definition of molecule should include monatomic entities such as noble gases. Unfortunately, all the commonly accepted definitions, including IUPAC's, require that molecules have at least two atoms. So that's what we must report in Wikipedia. -- Itub 20:13, 6 May 2007 (UTC)
Cacycle, you have just reverted the introductory section of that article to a vulnerable state that in the past had justified a long series of wild edits and contributions. The version you have modified was the result of a cooperative effort of capturing the essence of various definitions and aspects, and --rather than being stale-- it was relatively stable for a long period of time because of the achieved consensus. Please take a look at the history and the discussion page.
The IUPAC definition by itself is not sufficient for the broader scope of this article as it is given from the narrow perspective of theoretical chemistry. The multiple citations referenced by user:Sadi_Carnot as note 1 are proof of the wide inconsistence in defining a molecule among authoritative academia circles.
In science, a molecule is a sufficiently stable electrically neutral group of at least two atoms in a definite arrangement held together by strong chemical bondss. Only in the kinetic theory of gaseses the term molecule is often used for any gaseous particle regardless of their composition.
Also, the short discussion about divisibility that you have wiped was provided in support of that most general definition involving the "smallest particle..." and is of historical importance (see for ex. here as well as history of the molecule)
Molecules and atoms are the smallest particles of pure chemical substances that still retain their composition and chemical properties.
Also, it is incorrect to include NaCl in the discussion about network solids. That discussion was intended to differentiate the concepts of covalent vs. molecular.
No typical molecule can be defined for ionic ( salts) and covalent crystals ( network solids) which are composed of repeating unit cells that extend either in a plane (such as in graphite) or three-dimensionally (such as in diamond or sodium chloride).
I guess the general message here is that most things were included in the article for a reason, and hope you will reconsider your next edit, but for now I am revering to the mentioned version and would appreciate your discussing the intended contribution on the talk page-- Unconcerned 03:10, 1 May 2007 (UTC)
I think that the statement "The smallest molecular species that has a bond is the hydrogen ion molecule H2+, comprised of two protons bonded together by the sharing of one electron" is incorrect. I would assume that removing an electron would increase the bond length and thus H2+ would be larger in size than to nuetral H2. H2+ is the molecule with the least number of total electrons, however I am not sure why this is important. I think that this statement needs to be corrected or referenced. M stone 06:06, 25 May 2007 (UTC)
Something needs to be added to define molecular species, particularly molecular ions such as H2+ and common ions like sulfate. I'm not sure where though. Any ideas? -- Bduke 09:18, 8 June 2007 (UTC)
I thought that consensus was reached on H2+. It is confusing to talk about size in terms of the number of particles. H2 is the smallest molecule because it has the shortest bond length. H2+ is the simplest molecule because it is composed of the fewest number of particles. However, H2+ is larger than H2. I have changed things back to previous consensus. would appriciate if a bond length were found for H2+ before it was readded. M stone 19:35, 1 October 2007 (UTC)
I'm not sure I understand what Molecular compound is trying to say. I think it is meaning molecules and so anything new should be here. It apparently is to contrast with Ionic compound; but, I don't believe molecular compound is a common usage. ChemGardener 02:54, 22 June 2007 (UTC)
Moved to Talk:Human molecule. -- Sadi Carnot 14:30, 28 September 2007 (UTC)
In Molecular biology the "small molecule" name applies to organic molecule that are not biopolymers and that are not biologically inert (they are small as a consequence of not being a polymer). it redirects here, which is not good. So I will make an article and see what I can conjure up. Help very welcome. -- Squidonius ( talk) 23:47, 5 May 2008 (UTC)
I know a few elements that combine with others to form a molecule, like:
What other atoms/elements are there? Please awnser Androo123 ( talk) 19:45, 20 June 2008 (UTC)
I think that external links are all spam. I just noticed based on the most recent addition. I think they should all be erased. M stone ( talk) 10:56, 28 June 2008 (UTC)
"... a molecule is defined as a sufficiently stable, electrically neutral group..."
"The simplest of molecules is the hydrogen molecule-ion, H2+ ..."
P99am ( talk) 09:30, 24 April 2009 (UTC)
I think that the main problem is not in the hydrogen ion, but in the definition. It may be better to say:
Not "is defined".-- P99am ( talk) 12:57, 24 April 2009 (UTC)
Your definition is much better than given in this article. Nevertheless, it does not make clarity. And no one definition of the molecule create clarity. And it's good. We need explanations, not definitions.-- P99am ( talk) 15:24, 29 April 2009 (UTC)
molecules —Preceding unsigned comment added by 75.74.111.30 ( talk) 21:51, 26 August 2009 (UTC)
Can this image be added to this article? That is the best image of a molecule in existence. 85.65.69.166 ( talk) 03:15, 1 September 2009 (UTC)
image show now ¢$₯₣ — Preceding unsigned comment added by 39.32.88.30 ( talk) 17:57, 22 October 2013 (UTC)
i believe that an article about molecules should show at least 3-5 photos of molecules from microscopes... — Preceding unsigned comment added by 79.182.15.64 ( talk) 10:39, 19 September 2011 (UTC)
The text under this image is faulty. It states that the middle and left images are 3d, and that the right one is 2d. The problem is that the right one also is (partially) 3d. As you guys know the way the bonds are displayed gives information about the invisible z-axis. It's not very obvious and more of a wrong nuance, but I do think something should be changed.
Potential solutions are, change the text and change the image.
The information given by the text is valid and relevant, so I think it is preferable to change the image.
What do you guys think?
Bartiosos (
talk) 08:25, 12 February 2014 (UTC)
Ionic bonds: Molecules with ionic bonds are quite uncommonly encountered, sure gaseous sodium fluoride may be ionic and a molecule, but any liquids or solids that use ionic bonds will form networks, and not be molecular.
Target audience: Our target audience may be grade 6 or 7 students, so some of the more technical stuff needs more explaining. Perhaps we need more comparisons for scaling. Perhaps we need to give numbers of molecules (mols).
Referencing is poor, likely because our writers know this stuff, and do not neeed to look at a text book.
Categories of molecules.
Shapes of molecules (include symmetries)
properties as a gas.
Properties when condensed, liquids and solids
Graeme Bartlett ( talk) 10:13, 29 February 2016 (UTC)
I think that the statement in the article that organic chemists include polyatomic ions in the definition of "molecule" is, clearly, not supported, according to my experience in organic chemistry for 50 years. If this definition is found in one or two sources, it certainly should be considered an "outlier" ` Frankxxxx ( talk) 03:00, 26 November 2021 (UTC)
molecule is made up of more than one atom Balabharathi.v ( talk) 14:06, 2 December 2021 (UTC)
I have removed some irrelevnt info from lists of molecules i shall copy it here in case someone wants to incirpartate into this article:
Amedeo Avogadro created the word "molecule". [1] His 1811 paper "Essay on Determining the Relative Masses of the Elementary Molecules of Bodies" states, according to Partington's A Short History of Chemistry, that: [2]
The smallest particles of gases are not necessarily simple atoms, but are made up of a certain number of these atoms united by attraction to form a single molecule.
References
If two or more than two atoms combine to form molecule Then how is He Ne molecule as they are monoatomic and no atoms are combined??? The right definition of molecule is the smallest particles of matter which can exist independently as separate unit Asadalimukhlis ( talk) 03:47, 20 May 2023 (UTC)
This article is currently the subject of a Wiki Education Foundation-supported course assignment, between 12 February 2024 and 14 June 2024. Further details are available on the course page. Student editor(s): GiaTran21 ( article contribs).
— Assignment last updated by GiaTran21 ( talk) 23:22, 11 March 2024 (UTC)