eV , how much is it?

[DrDoggy]

HI ALL!

Im trying to understand ionization energy, which as i understand is the amount of energy it takes to bump these electrons out of orbit, first i have problems measuring a gram of O2, so lets start simple with NaCl:
Na = 500 KJ/mol = 5eV
Cl = 1250 KJ/mol = 13eV
so if i want to break down this compound I would go by the Na value rite? since it is the first in the compound?
1 mol of Na requires 500KJ so thats what i need to dump in to my pot, but how?

according to this: http://www.rapidtables.com/calc/electric/Joule_to_Watt_Calculator.htm
If i am to dump 500KJ to get my mol of na i will need to insert electric power at 1.6KWatt for 5 minutes? or 800watts for 10 minutes?
in order to set that value though i need to know 2/3 of the following values: voltage, current, resistance, but what is the best way to do this? could I use a volt divider to bring down the KV value for my voltmeter...?
but how should i get my other value(s) , what would be easiest method? is it safe to put kv(low amps) on my ammeter? and how do I measure high resistance like that?

Also what is the point of stripping a second electron?
and with this energy level as an example what temperature can i expect in my core(between anode and cathode), so far the pot gets warm to the touch, but at the same time i show evidence of temperatures of over 800degrees on the inside?

 

am I right about these asumptions?

 

THANKS!

 

[Strange]

It is slightly more complicated than that. If I understand you correctly, you are looking at the energy to dissociate NaCl into its constituent elements. The dissociation energy can be calculated as shown here: http://hyperphysics.phy-astr.gsu.edu/hbase/molecule/boneng.html

 

If you wanted to try this (I wouldn't recommend it) you would need to melt the NaCl (by heating it to about 800C) and then use electrolysis to separate the sodium and chlorine. Both of these are dangerous chemicals so this is not advisable unless you know what you are doing. (And it doesn't seem as if you do.)

[DrDoggy]

Of course im fully trained in safty, and this salt idea is just for theory, but wait so dissociation energy is less than ionization?

also i am aware of second comment , but i am more interested in the energies!

Also true i know only basics on the chemistry of things but would like to understanted better about the energy levels involved, very nice link! but could you explain about where these energy values come from, and how to calculate?

in the h20 example:

 

A)where does 5.7eV come from?

B)and does this work? -----> 2H2O = 2H2 + O2 - 5.7eV (cos im putting sum in)

 

If you could explain how to do the math for this whole process from a-z-a for the water example and where you get those numbers , and then i would like to try for myself in the salt example

 

a-z-a = h2+o2 , ignition energy, energy out, water, energy requeired for back to h2+o2

 

THanks!

[Sensei]

1 eV = 1.60217657*10^-19 J

 

495.8 kJ/mol is still 495.8 kJ energy (500 kJ was approximation),

but 1 mol is 6.022141*10²³ molecules.

So if you want to calculate energy spend/released by single molecule, divide:

495.8 kJ / 6.022141*10²³ = 8.2329^-19 J

then if you divide by 1.60217657*10^-19 J

8.2329^-19 J / 1.60217657*10^-19 = 5.1386 eV

 

You will receive energy per single molecule, or atom, or particle.

 

But it's ionization energy of pure Sodium.

http://en.wikipedia.org/wiki/Ionization_energies_of_the_elements_%28data_page%29

 

If you could explain how to do the math for this whole process from a-z-a for the water example and where you get those numbers ,

 

Read electrolysis of water

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

Edited June 1, 2015 by Sensei

[DrDoggy]

OK I get it!~ so it is all about the bond Enthalpy , so really to break up water i add 5.7eV and to put it back together again i loose 5.7eV, correct?

but how many eV does it take for my bbq piezo lighter to do its trick to start the process, 5.7eV?

 

Also back to the salt:

 

Cl:Cl = -242 kj/mol bonding energy to split, but now what? i could not find a bond energy chart for sodium, to see Enthalpy, or does it need since Na is just Na and not Na2? also in the link i noticed that they did not add in the energy requeired to split Cl2.

[John Cuthber]

Of course im fully trained in safty, ...

 

 

LOL

[DrDoggy]

ok ya got me, so i may not be completely fully trained, but i do know:

to vent the chlorine

the rectivity to skin of sodium

not to lick my electrodes

and to do other safe things aswell,

 

 

I am fully equiped to run this expirment if i decide, my interest lies in how it works behind the scene, and i am too lazy to physically do it, espically if math can do it for me,i have been eager to learn this since I was a pup!

 

so if that is true:

2H2O = 2H2 + O2 - 5.7eV

then to generate that 5.7eV or 500Kj/mol I need to run electrolsys 1.6kw for 5 minutes to get 1 mol?

[DrDoggy]

If you wanted to try this (I wouldn't recommend it) you would need to melt the NaCl (by heating it to about 800C) and then use electrolysis to separate the sodium and chlorine. Both of these are dangerous chemicals so this is not advisable unless you know what you are doing. (And it doesn't seem as if you do.)

 

 

Also , I wonder what would happen if i invented a machine that could electrolysis salt without heating, would this be a hit item in the industry? i wonder who would buy it?

 

just wondering , cos i am able to,... also during my tests a purple residue showed up on my salt, what could be purple?

[Fuzzwood]

Then you would confirm that you know jack poo about thermodynamics.

[DrDoggy]

I will confirm that about anything, including electric current which i discovered when i stuck my finger in a wall wart,

 

So let me get this straight, every time someone wants to break up a salt crystal they put it in a oven before they electrocute it?

I need to know : specifically, who would waist time doing this>? Please explain how much energy they waste doing this?

also why dont they just dissolve the salt into water for electrolysis?

 

also please , tell me how much eV's do THEY need to break down that 1 mol of salt and how do I translate that to electric power?

also how/where do i find the electrical resistance of this salt stuff.?

also please explain why it smells like chlorine up in here?

Edited June 8, 2015 by DrDoggy

[Fuzzwood]

Depends what you want to do with the salt crystal. If you want smaller salt crystals, it goes in a grinder. If you want a solution of ions, you dump it into water. If you want to extract the sodium metal, then yes, you have to melt it and elektrolyze it.

[imatfaal]

http://www.scienceforums.net/topic/37193-no-you-cant-make-sodium/

[DrDoggy]

that makes sense Thanks,

also I have been reading this:

http://hyperphysics.phy-astr.gsu.edu/hbase/molecule/nacl.html

 

and i think i get this mostly now, but there is still one issue, if 5.1(Na) - 3.6(Cl) = 1.5eV , then why do i need to add so much heat???, plugging it in to this chart

http://www.colby.edu/chemistry/PChem/Hartree.html

1 ev = 1.60217657 × 10^-19 joules

or

1.5ev = 2.4 e-19 joules

2.4 e-19 joules = V * I * s

2.4 e-19 joules = V * 1.6e-19amps * s

2.4/1.6 = V * s

1.5 joules/amp = V * s

 

 

but NOW the part i dont get is why do i need to melt the salt, if all i need is 1.5v, which is my minimum for 1 second to split 1 molecule, as per calculation, also why cant I use 0.8Volts for 2 seconds to get the same effect,

 

also i wonder in the case examples of lasers and ionization shells and similar, in o2 plasma i see whiter shades of pink as i get closer to the electrode(anode), can i presume these are different energy level emissions? is there a way to determine what emissions i will get when adding energy to my elements/compunds?

 

for example i was told that i need to input around 2480ev to generate xrays, so thats a minimum of 2480volt for 1second.

but does that mean that if i apply 24.8 volts for 100seconds i will still get an xray out of it?

Also what happens if i need 2480 but only put in 2400V for 1second, will that energy get dumped as heat and/or light?

 

also back to the salt, if i apply 5 volt instead of 1.5volt what will happen, will the energy go towards splitting 3x fast , and 0.5 dumped to heat/light, also how do we know when it will be dumped to light or heat? or any other harmonic emission,,

 

Also with 1.5ev = V * s is there a minimum number s(econds) can be, ie what if s drops below the period time of emission, ie (1/frequency)??

Edited June 18, 2015 by DrDoggy

[Fuzzwood]

The issue is conductivity. Salt in its solid form does not conduct because there are no ions to conduct. Both salt in solution and salt in molten form has split into ions and thus can conduct.

[DrDoggy]

but my equation just told me that i only need 1.5v * s to do a split, for each single molecule

 

also this is important to me:

"with 1.5ev = V * s is there a minimum number s(econds) it can be, ie what if s drops below the period time of emission, ie (1/frequency)??"

would a single xray emission @ 2480eV shot at the salt then react to produce 2480/1.5 = 1653x salt molecules broken up?

[Fuzzwood]

Because there is more to this than just applying voltage. Perhaps you still might want to pick up that science book people suggested you did.

 

Also, I'd like to repeat imatfaal's link: http://www.scienceforums.net/topic/37193-no-you-cant-make-sodium/

Edited June 19, 2015 by Fuzzwood

[DrDoggy]

ohno, you cant trick me, only you have suggested reading a whole book which i prolly already did and could not find anything about this, in english anyway...EDIT:..... Maybe i choose the wrong book, I have first year chemistry, which year do you suggest i read?

 

I dont get why though as i have been told 1.5eV is what i need, which is also the minimum voltage i require to get a reaction, also , does the energy i wasted putting in to heat to melt it contribute to bring that 1.5eV value down?

Edited June 19, 2015 by DrDoggy

[studiot]

I don't have any idea where you 1.5 volts comes from, and your tone is not receptive towards help.

 

Anyway here is a table of first ionisation potentials in volts.

You will note that the first ionisation potential for sodium is 5.14 volts.

 

Edited June 19, 2015 by studiot

[John Cuthber]

Doggy,

You might start by reading this

https://en.wikipedia.org/?title=Nernst_equation

[DrDoggy]

THANKS, and im sorry to come across rough, i can accept criticism and being told im wrong, but only telling me to go back to school wastes time for us all , as well as the forum.

quote: Because there is more to this than just applying voltage.

This is what im trying to figure out, comments like that are just telling me what we all already know, not what i need to know, or at least what i need to research to figure it out for myself,

 

I have gotten that 1.5eV from this reference:

http://hyperphysics.phy-astr.gsu.edu/hbase/molecule/nacl.html

quote:

sodium only 5.14 electron volts of energy to remove that electron. The chlorine lacks one electron to fill a shell, and releases 3.62 eV when it acquires that electron (it's electron affinity is 3.62 eV). This means that it takes only 1.52 eV of energy to donate one of the sodium electrons to chlorine when they are far apart.

 

also i just realize that 1.52 is wrong since i forgot to add in the "coulomb attraction force" , is this a general value that is always applied, or does it change with

every atom/molcule?

 

Also pls confirm that your reference to "ionization potential" is the same as ionization energy, as per this link:

https://en.wikipedia.org/wiki/Ionization_energy

 

also according to this chart:

http://web.williams.edu/Astronomy/research/PN/nebulae/ionpotentials.jpg

47.3eV is the SECOND ionization energy, pls confirm.

and also please explain mathematically how you have derived 47.3 volt from that 47.3eV(this is what i dont understand)

 

edit:omitted question

Edited June 19, 2015 by DrDoggy

[studiot]

Don't forge that ionisation energy and ionisation potential is defined to the removal of one electron from the free atom in a gaseous state.

 

I costs quite a lot of energy to get that atom from its normal state, combined with chlorine in a lattice to this state.

 

The lattice energy of NaCl is 782.1 kJ/m

 

The heat of hydration is -777.8 kJ/m

 

 

so if i want to break down this compound I would go by the Na value rite? since it is the first in the compound?
1 mol of Na requires 500KJ so thats what i need to dump in to my pot, but how?

according to this: http://www.rapidtabl..._Calculator.htm
If i am to dump 500KJ to get my mol of na i will need to insert electric power at 1.6KWatt for 5 minutes? or 800watts for 10 minutes?
in order to set that value though i need to know 2/3 of the following values: voltage, current, resistance, but what is the best way to do this? could I use a volt divider to bring down the KV value for my voltmeter...?
but how should i get my other value(s) , what would be easiest method? is it safe to put kv(low amps) on my ammeter? and how do I measure high resistance like that?

 

The pidgin scientific English will not win friends and influence people, nor make them think you are serious.

 

If you are serious we can discuss apparatus commensurate with the definition of ionisation potential that will register the 5.14 volts on a (suitable) voltmeter in producing sodium ions and electrons.

[Strange]

but NOW the part i dont get is why do i need to melt the salt,

 

So it becomes electrically conducting.

 

if all i need is 1.5v, which is my minimum for 1 second to split 1 molecule, as per calculation

 

If you apply that voltage to an insulator (such as solid salt) for a week then nothing will happen.

 

I also don't know where this calculation comes from. It takes energy to dissociate an molecule or ionize an atom. Voltage is not energy.

 

for example i was told that i need to input around 2480ev to generate xrays, so thats a minimum of 2480volt for 1second.

 

No. eV is a measure of energy. volts is a measure of potential difference.

 

Also with 1.5ev = V * s

 

This equation is meaningless.

but only telling me to go back to school wastes time for us all , as well as the forum.

 

It clearly would not be a waste of time for you. There are some excellent online courses from high quality universities available for free. Check out Coursera for example.

 

 

I have gotten that 1.5eV from this reference:

http://hyperphysics....ecule/nacl.html

quote:

sodium only 5.14 electron volts of energy to remove that electron. The chlorine lacks one electron to fill a shell, and releases 3.62 eV when it acquires that electron (it's electron affinity is 3.62 eV). This means that it takes only 1.52 eV of energy to donate one of the sodium electrons to chlorine when they are far apart.

 

That is 1.5 eV not 1.5 V.

[DrDoggy]

in a gaseous state,... i always forget that, but now im confused, so i use ionization energy for gaseous emission spectrum, and lattice energy for electrolysis of liquids, but don't i use enthalpy for that?

and heat of hydration is the change in enthalpy when dissolved in water? in that case i will simplify and leave the water out.

 

I am still reading the Nernst equation , it looks like what im looking for but i will need to read in to it a bit more to understand it..

 

Also Imatfaal and Fuzworth i reread that link a 3rd & 4th time and I didn't realize that Na is a touchy subject, so i am going to steer this conversation away from this compound, I was merely using it since it seemed to be a common topic so was using it as reference to get broader help. I had no intention to stagnate you but was encouraging you to elaborate, and I like what you said in post 14 about conductivity, which is 1/resistance, but i question any compound having an infinity resistance. and would suspect that we can plot resistance vs temperature, or at least resistance vs density, or something like that. to which R>0 and would not hit that axis, also thanks i forgotten about NaOH.

 

Lots of great help guys! but maybe i should step back a bit,

 

I come from the world of electricity where p=vi and v=ir , and now energy=p*t! I have recently been taking interest in lasers where we get our tube of gas and based on that gas type a energy emission value is produced, in the example of the air laser, you get your color emission , but you also get ozone from ionizing the oxygen and lasers are very inefficient due to heat loss, the basic question is how do i establish the volts i need to apply which is dependent on resistance which i assumed is relative to things like pressure, temperature, volume, and the atom/molecule's energy shell factor. And how can i calculate how much of my total energy is being broken up between those different outputs.

 

Also it is funny and the first time i have ever heard my language called pidgin, but I do need to be careful of communication errors in here, from my standpoint energy and potential energy are different, but i will proceed in assuming that in chemistry IE and IP are similar.

[studiot]

That doesn't explain where you want to go next???

[DrDoggy]

Because there is more to this than just applying voltage.

 

basically i want to know what "more" is....

 

simply i need to know which chart i should be getting eV values from and how to establish what Voltage needs to be applied to split/ionize said given compound. with the factors that make up that value such as things like temperature, pressure, density. I'm not really sure about all factors in this equation..

(Im sorry if I'm making you repeat things, but im still unclear about which eV chart is which)

 

And if its possible how to predict how that energy i put in to the compound will react/dissipate, ie light, heat, chem reaction, ect..

Edited June 22, 2015 by DrDoggy