Reactive Phosphorous

[hazelm]

What does it mean to say an element is "reactive"?  A Wiki article says of phosphorous ".....because it is highly reactive, phosphorus is never found as a free element.

 

Thank you.

[Dubbelosix]

It simply means the half-life of the material is very low, and so unstable. In terms of reactivity, it can involve many factors, such as environment. 

[hazelm]

It simply means the half-life of the material is very low, and so unstable. In terms of reactivity, it can involve many factors, such as environment. 

Thank you. 

[exchemist]

What does it mean to say an element is "reactive"?  A Wiki article says of phosphorous ".....because it is highly reactive, phosphorus is never found as a free element.

 

Thank you.

Reiku (Dubbelosix) is talking rubbish.  This is nothing to do with radioactivity. This is an issue of chemistry.

 

Elemental phosphorus (note the spelling, by the way, it's not phosphorous) reacts with oxygen in the air, to the extent that it is pyrophoric (catches fire spontaneously).  Hence for instance the well-known use of "white phosphorus" as a rather nasty incendiary munition. 

 

In the laboratory elemental phosphorus is stored under water to stop this. (Not to be confused with reactive metals, such as sodium, which are stored under paraffin, as they react violently with water!)

 

A reactive material is one that readily undergoes chemical reactions. Phosphorus, especially the white variety has 3 single bonds to other P atoms. By forming the oxide P4O10, each phosphorus atoms has formed 5 strong bonds to oxygen (diagram here: https://en.wikipedia.org/wiki/Phosphorus_pentoxide#/media/File:Phosphorus-pentoxide-2D-dimensions.png), so it can lower its energy by forming the oxide.  

[hazelm]

Reiku (Dubbelosix) is talking rubbish.  This is nothing to do with radioactivity. This is an issue of chemistry.

 

Elemental phosphorus (note the spelling, by the way, it's not phosphorous) reacts with oxygen in the air, to the extent that it is pyrophoric (catches fire spontaneously).  Hence for instance the well-known use of "white phosphorus" as a rather nasty incendiary munition. 

 

In the laboratory elemental phosphorus is stored under water to stop this. (Not to be confused with reactive metals, such as sodium, which are stored under paraffin, as they react violently with water!)

 

A reactive material is one that readily undergoes chemical reactions. Phosphorus, especially the white variety has 3 single bonds to other P atoms. By forming the oxide P4O10, each phosphorus atoms has formed 5 strong bonds to oxygen (diagram here: https://en.wikipedia.org/wiki/Phosphorus_pentoxide#/media/File:Phosphorus-pentoxide-2D-dimensions.png), so it can lower its energy by forming the oxide.  

Oops!  Sorry about that spelling.  Can it be fixed?  Thanks.  Now to read the rest. 

[hazelm]

Reiku (Dubbelosix) is talking rubbish.  This is nothing to do with radioactivity. This is an issue of chemistry.

 

Elemental phosphorus (note the spelling, by the way, it's not phosphorous) reacts with oxygen in the air, to the extent that it is pyrophoric (catches fire spontaneously).  Hence for instance the well-known use of "white phosphorus" as a rather nasty incendiary munition. 

 

In the laboratory elemental phosphorus is stored under water to stop this. (Not to be confused with reactive metals, such as sodium, which are stored under paraffin, as they react violently with water!)

 

A reactive material is one that readily undergoes chemical reactions. Phosphorus, especially the white variety has 3 single bonds to other P atoms. By forming the oxide P4O10, each phosphorus atoms has formed 5 strong bonds to oxygen (diagram here: https://en.wikipedia.org/wiki/Phosphorus_pentoxide#/media/File:Phosphorus-pentoxide-2D-dimensions.png), so it can lower its energy by forming the oxide.  

So, "never found as a free element" may be saying that phosphorus reacts with nearly anything and everything.  I understand the reaction when it explodes into flames.  The two elements are (my terms) "at war".  They do not combine, at least not into a simple compound.  Right?

 

But, how about it joining other elements to form simple compounds?  Do we say elements "react" when they form compounds?

 

I think we have phosphorus in our bones?  I am remembering something about why Cola drinks cause leg cramps.  Phosphorus is involved.  Also calcium and one other that I have forgotten.

 

Thank you.

[Dubbelosix]

Exchemist these days takes any attempt to attack me, I hardly ever bother him, but he hates it when I get the smallest bit of attention. It depends on how you look at the situation. Highly reactive chemicals do not last long, they simply burn their energy away. Oxidization is a perfect example of why you cannot get certain types of matter in free form in nature. They simply do not last a long time. It may not be safe to say they are technically free, as it depends on the way you contain an element. Lithium and Sodium are two good examples of reactive materials and to stop reactivity you can store certain chemicals in oil to prevent things like oxidization.

[exchemist]

So, "never found as a free element" may be saying that phosphorus reacts with nearly anything and everything.  I understand the reaction when it explodes into flames.  The two elements are (my terms) "at war".  They do not combine, at least not into a simple compound.  Right?

 

But, how about it joining other elements to form simple compounds?  Do we say elements "react" when they form compounds?

 

I think we have phosphorus in our bones?  I am remembering something about why Cola drinks cause leg cramps.  Phosphorus is involved.  Also calcium and one other that I have forgotten.

 

Thank you.

No oxygen and phosphorus are not "at war",  they love each other dearly and give off heat when they get together. The product of the reaction is phosphorus pentoxide, empirical formula P2O5 but molecular formula P4O10, as shown in the diagram I linked to. Phosphorus pentoxide in the presence of water forms phosphoric acid (H3PO4) and it is the ions from this, phosphate ions, (PO4 3-)  and variants of them, that we find in our bones and in fact throughout biochemistry. 

 

Phosphorus in these compounds is joined to oxygen and is thus quite docile in this form :)  

[hazelm]

No oxygen and phosphorus are not "at war",  they love each other dearly and give off heat when they get together. The product of the reaction is phosphorus pentoxide, empirical formula P2O5 but molecular formula P4O10, as shown in the diagram I linked to. Phosphorus pentoxide in the presence of water forms phosphoric acid (H3PO4) and it is the ions from this, phosphate ions, (PO4 3-)  and variants of them, that we find in our bones and in fact throughout biochemistry. 

 

Phosphorus in these compounds is joined to oxygen and is thus quite docile in this form :)

I was thinking of this quote:  "Elemental phosphorus (note the spelling, by the way, it's not phosphorous) reacts with oxygen in the air, to the extent that it is pyrophoric (catches fire spontaneously).  Hence for instance the well-known use of "white phosphorus" as a rather nasty incendiary munition."

 

Depends on your definition of "love"?  :-)  I think I am a bit confused here. 

 

 

And a little research reminded me that phosphoric acid is in the colas.  It is consumption of too much cola that joins up with what is in our bones and overwhelms the calcium, weakening the bones.

Edited January 14, 2019 by hazelm

[hazelm]

Normally, I'd not put this in Chemistry but I want to see if "reactivate" is the same as "reactive".  And since the issue started in Chemistry,  this seems the better place.

 

https://www.sciencedaily.com/releases/2019/01/190117142115.htm

 

Scientists learn how common virus reactivates after transplantation.  Antibody-producing B cells, not disease-fighting T cells protect against reactivation of cytomegalovirus.

 

My take:  "reactive" and "reactivate" = something changing to do differently than what we normally expect of it.  Are these two the same word, one as an adjective and one as a verb?

 

Or, does reactivation simply mean cytomegalovirus - which remains in the body for life once one is infected - becomes active again, causing new problems.

 

I am sorry to drag this out but I still have questions about "reactive" as in the OP. 

 

Thank you.

Edited January 19, 2019 by hazelm

[exchemist]

Normally, I'd not put this in Chemistry but I want to see if "reactivate" is the same as "reactive".  And since the issue started in Chemistry,  this seems the better place.

 

https://www.sciencedaily.com/releases/2019/01/190117142115.htm

 

Scientists learn how common virus reactivates after transplantation.  Antibody-producing B cells, not disease-fighting T cells protect against reactivation of cytomegalovirus.

 

My take:  "reactive" and "reactivate" = something changing to do differently than what we normally expect of it.  Are these two the same word, one as an adjective and one as a verb?

 

Or, does reactivation simply mean cytomegalovirus - which remains in the body for life once one is infected - becomes active again, causing new problems.

 

I am sorry to drag this out but I still have questions about "reactive" as in the OP. 

 

Thank you.

No these are quite different words.

 

Reactive, means prone to "react", which in chemistry mean prone to combine with other substances, in a chemical reaction. Phosphorus is prone to react with oxygen for instance. 

 

Reactivate mean to make active once more something that is not active. 

[hazelm]

No these are quite different words.

 

Reactive, means prone to "react", which in chemistry mean prone to combine with other substances, in a chemical reaction. Phosphorus is prone to react with oxygen for instance. 

 

Reactivate mean to make active once more something that is not active. 

Thank you.  That was what was coming to me eventually for "reactivate".   And, with "reactive",  I have a special chemistry definition - prone to combine with other substances.  That was my main confusion - the chemistry definition.  I was stuck on the more common definition.  I'll skip it.  I have this now.  I appreciate your patience.  Back to work.

[GAHD]

Just to add my 2 bits in a way that might be informative:

Dubbleosix's first post must indeed be talking about something completely unrelated. They might be decent with math, but they seem to be completely mixing up terminologies. "half-life of the material" has nothing at all to do with reactivity. Half life generally refers to nuclear decay rates, the changing of one element into others via weak force interaction, resulting in eventual spontaneous fission events and well known(for the most part) decay chains. THIS is what phosphorous half-life looks like, and other than REALLY strange isotopes that are themselves part of another decay chain has nothing at all to do with why you don't find it in elemental form. The second post by dubbs DOES follow the topic though: REDOX is very much applicable. 

Aluminum is another example of an element that is very reactive and difficult to find/keep in pure form. Al reacts with oxy in the air in fractions of a second, resulting in an aluminum-oxide layer on the surface(ruby/sapphire) that temporarily protects the refined metal beneath from further reaction. Abrasion and stress of that layer eventually contaminates any Al completely, so very similar to phosphorous "natural" aluminum is found bound-up with other elements. It's actually REALLY rare to find pure elements of any kind anywhere: everything likes to be neutral. Naturally neutral elements are the exception, rather than the rule down here on this rock we call earth(eg noble gasses).

On viral reactivation, that's both the same and different. In this case "reactivation" seems to be a poor  word choice by the writer/journalist. I think "relapse" and/or "propagation" would have better conveyed what's going on. AFAIK "reactivation" should be reserved for instances where a destroyed virus spontaneously self-(re)assembles from a bunch of component parts left free-floating in plasma that would normally be filtered and excreted as waste. Think there was a big flush of research on THAT topic back in '14-15 era. EG. It's one of the few things that's actually worrisome about some immunization methods, as the "broken/weakened" viral material used in inoculation CAN fully reactivate and/or spontaneously mutate in the right conditions. That right there is organic chemistry and quite a bit more nuanced and complex than basic chemistry. The way I read it, that article is more a study on how marker proteins play a pivotal role in maintaining suppression of an active infection, which in of itself is an immunology topic that has a LOT of flow-charting to get a good grasp on.

 

Edited January 20, 2019 by GAHD
P decay chain link, Weak force link

[exchemist]

Just to add my 2 bits in a way that might be informative:

 

Dubbleosix's first post must indeed be talking about something completely unrelated. They might be decent with math, but they seem to be completely mixing up terminologies. "half-life of the material" has nothing at all to do with reactivity. Half like generally refers to nuclear decay rates, the changing of one element into others via weak force interaction, resulting in eventual spontaneous fission events and well known(for the most part) decay chains. The second post by dubbs DOES follow the topic though: REDOX is very much applicable. 

 

Aluminum  is another example of an element that is very reactive and difficult to find/keep in pure form. Al reacts with oxy in the air in fractions of a second, resulting in an aluminum-oxide layer on the surface(ruby/sapphire) that temporarily protects the refined metal beneath from further reaction. Very similar to phosphorous, "natural" aluminum  is found bound-up with other elements. It's actually REALLY rare to find pure elements of any kind anywhere: everything likes to be neutral. Naturally neutral elements are the exception, rather than the rule down here on this rock we call earth(eg noble gasses).

 

On viral reactivation, that's both the same and different. In this case "reactivation" seems to be a poor  word choice by the writer/journalist. I think "relapse" and/or "propagation" would have better conveyed what's going on. AFAIK "reactivation" should be reserved for instances where a destroyed virus spontaneously self-(re)assembles from a bunch of component parts left free-floating in plasma that would normally be filtered and excreted as waste. Think there was a big flush of research on THAT topic back in '14-15 era. EG. It's one of the few things that's actually worrisome about some immunization methods, as the "broken/weakened" viral material used in inoculation CAN fully reactivate and/or spontaneously mutate in the right conditions. That right there is organic chemistry and quite a bit more nuanced and complex than basic chemistry. The way I read it, that article is more a study on how marker proteins play a pivotal role in maintaining suppression of an active infection, which in of itself is an immunology topic that has a LOT of flow-charting to get a good grasp on.

 

 

This set me thinking which elements are found in elemental form in nature. Noble gases obviously, but also oxygen and nitrogen. Carbon too (as diamond) and sometimes sulphur (around volcanic vents).  Gold, platinum and I think sometimes copper are found as metals.  Any others? 

 

For me the odd one out is really oxygen. Given its propensity to react, one might not have expected to find it occurring in elemental form. I presume we have photosynthesis to thank for that, by building carbohydrates from CO2 and water and giving off oxygen - an "uphill" process relying on light from the sun to drive it.  

[hazelm]

Just to add my 2 bits in a way that might be informative:

 

Dubbleosix's first post must indeed be talking about something completely unrelated. They might be decent with math, but they seem to be completely mixing up terminologies. "half-life of the material" has nothing at all to do with reactivity. Half life generally refers to nuclear decay rates, the changing of one element into others via weak force interaction, resulting in eventual spontaneous fission events and well known(for the most part) decay chains. THIS is what phosphorous half-life looks like, and other than REALLY strange isotopes that are themselves part of another decay chain has nothing at all to do with why you don't find it in elemental form. The second post by dubbs DOES follow the topic though: REDOX is very much applicable. 

 

Aluminum is another example of an element that is very reactive and difficult to find/keep in pure form. Al reacts with oxy in the air in fractions of a second, resulting in an aluminum-oxide layer on the surface(ruby/sapphire) that temporarily protects the refined metal beneath from further reaction. Abrasion and stress of that layer eventually contaminates any Al completely, so very similar to phosphorous "natural" aluminum is found bound-up with other elements. It's actually REALLY rare to find pure elements of any kind anywhere: everything likes to be neutral. Naturally neutral elements are the exception, rather than the rule down here on this rock we call earth(eg noble gasses).

 

On viral reactivation, that's both the same and different. In this case "reactivation" seems to be a poor  word choice by the writer/journalist. I think "relapse" and/or "propagation" would have better conveyed what's going on. AFAIK "reactivation" should be reserved for instances where a destroyed virus spontaneously self-(re)assembles from a bunch of component parts left free-floating in plasma that would normally be filtered and excreted as waste. Think there was a big flush of research on THAT topic back in '14-15 era. EG. It's one of the few things that's actually worrisome about some immunization methods, as the "broken/weakened" viral material used in inoculation CAN fully reactivate and/or spontaneously mutate in the right conditions. That right there is organic chemistry and quite a bit more nuanced and complex than basic chemistry. The way I read it, that article is more a study on how marker proteins play a pivotal role in maintaining suppression of an active infection, which in of itself is an immunology topic that has a LOT of flow-charting to get a good grasp on.

 

 

It is all another case of different people having different meanings for words and a common decision not being made.  That is why "reactive" confused me.  It has so very many definitions that are unrelated to each other.  I have had to constantly remind myself to think of the area of study that is being talked about.  The chemistry definition ot phosphorus combining with oxygen is quite different from the common meaning of two things or creatures reactng to each other.

 

There is another word for 'reactivate that I thought of yesterday but it is gone now.  It is also said of chicken pox virus and shingles. "Reawaken" makes more sense from a comprehension standpoint but there's a better word.  Somehow, "reactivate" requires an outside agent to do the awakening.  That is not usually happening with chicken pox or cytomegatovirus.

 

As for elements decaying into other elements, a story about the Curies says that uranium could decay into lead.  I keep thinking of the fact that uranium can be so harmful and, lead is actually used to seal up something harmful so that it does no harm.  An interesting combination is uranium and lead.  No?

[exchemist]

It is all another case of different people having different meanings for words and a common decision not being made.  That is why "reactive" confused me.  It has so very many definitions that are unrelated to each other.  I have had to constantly remind myself to think of the area of study that is being talked about.  The chemistry definition ot phosphorus combining with oxygen is quite different from the common meaning of two things or creatures reactng to each other.

 

There is another word for 'reactivate that I thought of yesterday but it is gone now.  It is also said of chicken pox virus and shingles. "Reawaken" makes more sense from a comprehension standpoint but there's a better word.  Somehow, "reactivate" requires an outside agent to do the awakening.  That is not usually happening with chicken pox or cytomegatovirus.

 

As for elements decaying into other elements, a story about the Curies says that uranium could decay into lead.  I keep thinking of the fact that uranium can be so harmful and, lead is actually used to seal up something harmful so that it does no harm.  An interesting combination is uranium and lead.  No?

I looked this up. It seems lead has both a "magic number" of protons (82) and also, in the case of the 208 isotope, a "magic number" of neutrons (126) in its nucleus.

 

Nuclei with these magic numbers appear to be particularly stable, in a manner analogous to the stability of the filled shells of electrons in noble gases. 

 

Lead appears to be the end point of a number of radioactive decay cascades, including, as you say, that of uranium.

 

Lead is also very useful as a shield against γ-rays and X-rays, because it has a high atomic mass and a high density, meaning there are lots of atoms per unit volume to intercept the rays.

 

The reason for the high density is itself interesting, if you are a chemist. :)  Lead atoms are relatively small in relation to the atomic number, due to something called the "lanthanide contraction". Unlike its lighter brother tin, lead does not directly follow a row of transition elements in the Periodic Table but only after  both a set of 14 lanthanides and a set of transition elements. As a result, the +ve charge on the nucleus has gone up 14 units more by the time you get to lead. However the 14 extra electrons are in f orbitals and these do not shield the outermost electrons from the nucleus very much, due to the shape of f orbitals. So the charge on the nucleus pulls in the outermost electrons (in p orbital) so much that the atom is not much bigger than that of tin. This is why lead is so dense.  The lanthanide contraction plays a big role in modifying the properties of the elements that follow the lanthanides. 

 

So, as usual, the explanation of the chemistry relies on quantum mechanics, in this case the shapes of atomic orbitals, which are the various "harmonics" of standing wave patterns.  

Edited January 21, 2019 by exchemist

[hazelm]

I looked this up. It seems lead has both a "magic number" of protons (82) and also, in the case of the 208 isotope, a "magic number" of neutrons (126) in its nucleus.

 

Nuclei with these magic numbers appear to be particularly stable, in a manner analogous to the stability of the filled shells of electrons in noble gases. 

 

Lead appears to be the end point of a number of radioactive decay cascades, including, as you say, that of uranium.

 

Lead is also very useful as a shield against γ-rays and X-rays, because it has a high atomic mass and a high density, meaning there are lots of atoms per unit volume to intercept the rays.

 

The reason for the high density is itself interesting, if you are a chemist. :)  Lead atoms are relatively small in relation to the atomic number, due to something called the "lanthanide contraction". Unlike its lighter brother tin, lead does not directly follow a row of transition elements in the Periodic Table but only after  both a set of 14 lanthanides and a set of transition elements. As a result, the +ve charge on the nucleus has gone up 14 units more by the time you get to lead. However the 14 extra electrons are in f orbitals and these do not shield the outermost electrons from the nucleus very much, due to the shape of f orbitals. So the charge on the nucleus pulls in the outermost electrons (in p orbital) so much that the atom is not much bigger than that of tin. This is why lead is so dense.  The lanthanide contraction plays a big role in modifying the properties of the elements that follow the lanthanides. 

 

So, as usual, the explanation of the chemistry relies on quantum mechanics, in this case the shapes of atomic orbitals, which are the various "harmonics" of standing wave patterns.  

It's  over my head but I want to work on it. I am wondering if it is lead that patients are protected from when undergoing CAT scans.  It must be powerful since the technicians leave the room during the process.  Did you know that, at one time, radioactivity was considered beneficial to our well-being?  And Marie Curie died of leukemia.  "Radioactive mineral springs" - a vacation spot.

 

Last night, just by coincidence, I read the story of how lead got into  gasoline - and how it got out again amid horrible protests from those getting rich on ethyl gasoline.  I do remember how people wanted ethyl gasoline if they could afford  the extra cost.  It prevented knocking in the engine. Then there are/were chlorofluorocarbons.  Same story.  ("A Short History of Nearly Everything" by Bill Bryson.)

 

By the way are these elements that other elements decay into all isotopes?