[sameeralord]

Hello guys

I don't know I just had a memory blank today. What I was wondering is lets say there is H⁺ ions in a container. So this means H has lost an electron. Where has this electron gone?

We take H₊ and Cl^- react to make HCl. How can this happen. I mean if  ^H+ means already lost an electron and Cl^- means they have already gained an electron. So isn't H⁺ and Cl- stable in terms of outershell electrons. Why do they have to react. I know when HCl is formed H donates a proton and Cl accepts it but how can this be done when H⁺ indicate that they have already lost an electron.

I mean the only way HCL can be produces is if H and Cl react not the ions.

You might be wondering I must be a really bad chem student but sorry this just popped up to my head today. Any help would be appreciated. 

[cliverlong]

<< snip >>

 I mean if  ^H+ means already lost an electron and Cl^- means they have already gained an electron.

I have found the bond in HCl tricky in the past. I think I follow your reasoning but may be it is a bit easier to start by considering a more "purely" ionic compound such as sodium chloride. I will explain why I suggest that at the end

Read up on

electrostatic attraction (without specific reference to atoms)

then

ionic bonding

Then try your following question again but consider sodium and chlorine

So isn't H⁺ and Cl^- stable in terms of outershell electrons. Why do they have to react?

I'm not quite clear what you mean by the following

I know when HCl is formed H donates a proton and Cl accepts it but how can this be done when H⁺ indicate that they have already lost an electron.

. but maybe after reading about electrostatic attraction and ionic bonding if you then read about the electronic structure of sodium and chlorine and think what that means in the following steps

sodium and chlorine atoms >> sodium and chlorine ions >> ionic bond

that might help in sorting out, in a simplistic way, the difference between forming the ions and the bonding that results. The "making of outer shells" is really only a simple "explanation" for a limited range of molecules that gets modified and discarded when other compunds are studied - but it is a start for explaining why atoms bond.

You asked about "what happens to the electron?"

Well if A becomes A⁺ and B becomes B^- what do you think happens to the electron and what is the effect of this?

Now ... back to your original example ... when I was at school, the term "anomalous nature of hydrogen" was much bandied about.

Basically (as I understand) bonds between hydrogen and other elements can have a range of ionic and covalent character

Wiki

http://en.wikipedia.org/wiki/Hydrogen_chloride

states that hydrogen chloride has a covalent not ionic bond even though upon dissolving in water the bond splits to form ions, H⁺ and Cl^- (and further, H⁺ links with one or more H₂0 molecules to form complexes normally represented as H₃O⁺ - there is a good thread on that subject in this forum about a week ago - I will try and find link)

So your original explanation of forming H⁺ and Cl^- ions, as a step in producing HCl and explaining the nature of the bond, doesn't actually apply in the case of HCl. Although I don't know how to explain how the bond actually is formed. Can someone help?

I never clearly understood what it is about the relationship between hydrogen and chlorine that makes the bond covalent rather than ionic (maybe something to do with electrode/reduction potential) . Hopefully someone else can explain why the bond in the molecule is covalent. I can explain how the bond works by electron sharing but not why.


Regards

Clive

[Astrokel]

I mean the only way HCL can be produces is if H and Cl react not the ions.

Both hydrogen and chlorine exists as diatomic they don't exist like just H and Cl. Hydrogen Chloride gas reacts with water to form hydrochloric acid,
 HCl + H₂O → H₃O⁺ + Cl⁻

The product is what is commonly known as HCl(aq). In hydrogen chloride HCl(g), H⁺ and Cl^- are connected through a covalent bonding, and this is because hydrogen shares its electron together with the electron shared by chlorine such that both are duplet and octet happy rspectively.

You can't just produce HCl(g) by reacting H+ and Cl- because it's not like ionic bonding, and in order to produce HCl there are other methods such as Cl₂ + H₂ → 2HCl(g)

So isn't H⁺ and Cl^- stable in terms of outershell electrons. Why do they have to react.

H₂ gas formed H⁺ and Cl₂ to Cl^- because of the existence of the single covalent bond between them. The bond is already present and you cannot just separate the H and Cl and say they are stable, because it is the bond that makes it stable.

[sameeralord]

Thank you Clivelong and Astrokel for your help.  So what about aqueous HCl. Ok let's take the example of NaCl. Na +  and CL -  ===== NaCl

So in this case does Na+ mean it has already lost an electron or has the potential to lose the electron.

You know my question is Na+ mean already lost an  electron. Does that mean it lost the electron to Cl. Making Cl- and Na+. So why does NaCl have zero charge. Is it because they balance out.

In this one

NH3 + H+  ====== NH4

In this case does H+ mean already lost an electron or has the potential to lose the electron. In this case has the H+ already lost an electron to some other element not NH3 and there is an acid base reaction by which NH3 gains H+.

So my basic question is this + and - we put do they mean electron is lost or gained or has the potential to do so. To do they mean both in different situations as I have shown?

[Astrokel]

hey!

You know my question is Na+ mean already lost an  electron. Does that mean it lost the electron to Cl. Making Cl- and Na+. So why does NaCl have zero charge. Is it because they balance out.

Yes

NH3 + H+  ====== NH4

Notice nitrogen in NH3 has a lone pair of electron(behaving like negative species) and as such NH3 get protonated to form NH4+. + indicates that al electron has been lost and - indicates an outer electron have been gained.

To do they mean both in different situations as I have shown?

[sameeralord]

Thanks a lot Astrokel.  I had a think about what you guys have said and I   think I understand now but I got few more problems

Is an ion stable or not?

Ion's have stable valence outershell hence I think they are stable. So why do they react to form NaCl. Is it simply because unlike charges attract and not actually to be stable. I mean if Na+ exist by itself is it fair to say it is stable.

My other questions is how can a solution of NaCl dissocitae to Na+ and Cl-. Wouldn't they attract like magnets forming NaCl again.

To summarise I'm thinking that ionic bonding is the attraction between opposite charges but this bonding not nessecaraly done to have a stable compound. I mean as I said ions (example Na+ can exist by itself and be
 stable. Am I right?

[Astrokel]

Yes you are right, if an ion have stable electronic configuration then it is pretty stable.

The ions such as Na+ and Cl- combines to form NaCl because sodium chloride has a lower energy than the ions exist by itself. In other words, heat is given off(exothermic, spontaneous, because of the strong ionic bonding) and NaCl is relatively more stable than its free ions.

To answer your question, you can read up on solvation, basically in order to dissociate the solid NaCl to its free ions, a polar solvent is needed, such as water. Water molecule will form its partial negative end to the cation and partial positive end to the anion, therefore dissociation takes place. http://en.wikipedia.org/wiki/Solvation

NaCl(aq) ----> Na+(aq) + Cl-(aq)

You cannot get a solution containing Na+ only, because it is impossible to 'extract' the ion from sodium chloride solution. At the most, you can only precipitate out the ion such as adding AgNO3 to precipitate the chloride ion, but still you get Ag+ and Cl- in the end. Basically, it's impossible to isolate just one single ion. In many reactions, one of the ion taking part in the reaction as spectator ion and the other undergo reaction, so you can safely regard only one of the ion(either cation or anion) taking part in the reaction, this is somehow like 'isolating' the ion.

[cliverlong]

Is an ion stable or not?

Well, it must be. If you have read up about sodium chloride and solvation as described by Astrokel, the Na⁺ and Cl^- ions exist in two environments, 1) held in giant ionic lattice where ions are not free to move - so does NOT conduct electricity and 2) in aqueous solution where the ions are free to move so DOES conduct electricity

Ion's have stable valence outershell hence I think they are stable. So why do they react to form NaCl. Is it simply because unlike charges attract and not actually to be stable.

Did you read up about electostatic attraction and ionic bonding?

Why do you think ions are not stable? If you can express that, maybe we can unlock your thinking on that.

I mean if Na+ exist by itself is it fair to say it is stable.

As Astrokel wrote, in solid or in solution the Na⁺ will not exist on its own

My other questions is how can a solution of NaCl dissocitae to Na+ and Cl-. Wouldn't they attract like magnets forming NaCl again.

As Astrokel wrote, its about the energy released up solvation - read up on that. I think entropy and inally "free energy" is also involved but start with enthalpy. There is a balance between the energy required to split up the NaCl and the (free) energy released by the process of solvation.

You don't have to think about "attract like magnets" if you have read up on electrostatic attraction.

To summarise I'm thinking that ionic bonding is the attraction between opposite charges

Yes

but this bonding not nessecaraly done to have a stable compound.

Why do you write that? You are right - but I think for the wrong reason. Please give an example of what you mean.

I mean as I said ions (example Na+ can exist by itself and be  stable. Am I right?

As Astrokel wrote. Where do you think Na+ "exists on its own" ? This is not an interrogation. I'm just trying to understand why you think that - as that idea keeps on popping up in your writing.


Clive

[sameeralord]

You cannot get a solution containing Na+ only, because it is impossible to 'extract' the ion from sodium chloride solution. At the most, you can only precipitate out the ion such as adding AgNO3 to precipitate the chloride ion, but still you get Ag+ and Cl- in the end. Basically, it's impossible to isolate just one single ion. In many reactions, one of the ion taking part in the reaction as spectator ion and the other undergo reaction, so you can safely regard only one of the ion(either cation or anion) taking part in the reaction, this is somehow like 'isolating' the ion.

You read my mind there  . I was thinking the same thing about spectator  ions and I was going to ask if what I thought about their role was right. It seems right  . Thanks 

Where do you think Na+ "exists on its own" ? This is not an interrogation. I'm just trying to understand why you think that - as that idea keeps on popping up in your writing.

Clive

Yeah it is true that Na+ can't exist on its own in nature. For an ion to exist there should be another ion where it can give or gain nessecary electrons from it. Right?

After the dissociation is it possible to filter the Na+ ions without using spectator ions. Is their anyway that humans can separate ions not by nature.

Is the reason that ion cann't exist by itself is because it doesn't have another atom to donate or gain nessecary electrons and be an ion in the first place. Is this the reason?

Another question lets say NaCl (aq) + KI (aq)  react. The products would be NaI and KCl. Why does Na react with I why can not it just recombine with Cl and not take part in a reaction. I mean if all the ions in this reaction are surrounded by water molecules how can they react?

I almost got it now. Few question still remaining. Also thanks for your response it was very helpful 

[Astrokel]

Hey sameeralord!

After the dissociation is it possible to filter the Na+ ions without using spectator ions. Is their anyway that humans can separate ions not by nature.

Honestly, i have no idea how to separate out the ions, perhaps it can be done through some magenetic field, i don't know!  Because imagine it is pretty difficult to separate 6.02 x10^23 ions in 1 mole. As far as my knowledge goes, it is quite limited (I'm taking my A level this year), sorry!

Is the reason that ion cann't exist by itself is because it doesn't have another atom to donate or gain nessecary electrons and be an ion in the first place. Is this the reason?

You mean a solution containing a single ion only? If so, yes.

Another question lets say NaCl (aq) + KI (aq)  react. The products would be NaI and KCl. Why does Na react with I why can not it just recombine with Cl and not take part in a reaction. I mean if all the ions in this reaction are surrounded by water molecules how can they react?

Will that reaction even take place? Both products are pretty soluble.

[sameeralord]

Yeah you are right. The products would be aqeous. So what is the point 
My questions are almost over now 

So one last clarification

There can't be a pure solution of Na + atoms in nature because Na atoms should have some other atom to gain or lose electrons to become an ion in the first place?

Just to clarify because I don't know if you mean single atom or single type in your answer.

You know one of the best things that came out of this topic for me. I finally understand the role of the spectator ions.  I never really understood their role and had no respect for them. Now I can see they are their to create the ions.

[Astrokel]

hey!!

There can't be a pure solution of Na + atoms in nature because Na atoms should have some other atom to gain or lose electrons to become an ion in the first place?

yes you are right!

[sameeralord]

hey!!

There can't be a pure solution of Na + atoms in nature because Na atoms should have some other atom to gain or lose electrons to become an ion in the first place?

yes you are right!

Another topic concluded then  Thanks once again for Astrokel and Clivelong for helping me once again. 

Finally I can treat the spectator ions with respect