[maakii]

yes. If for the reaction

X + e- >X-

delta H is lets say -250kJ /mol,

EGE =            -250kJ / mol
EA = -EGE =    250kJ /mol

[abcc]

yes. If for the reaction

X + e- >X-

delta H is lets say -250kJ /mol,

EGE =            -250kJ / mol
EA = -EGE =    250kJ /mol

that means they have the same meaning, but not the same???

[maakii]

Actually EA is just the delta H of the reaction:

X- > X + e-

According to the IUPAC gold book. So it would be negative of EGE ( delta H when reaction X + e- -> X- takes place) , which is the reaction taking place in the other direction.

[abcc]

Actually EA is just the delta H of the reaction:

X- > X + e-

According to the IUPAC gold book. So it would be negative of EGE ( delta H when reaction X + e- -> X- takes place) , which is the reaction taking place in the other direction.

??
electron affinity----- X+ e- > X-

[english]

First EA is negative, not positive.  I don't trust Wikipedia.

[maakii]

You should trust the IUPAC gold book then 

http://goldbook.iupac.org/E01977.html

[english]

You should trust the IUPAC gold book then 

http://goldbook.iupac.org/E01977.html

Yes, it says it is negative as well:

The equivalent more common definition is the energy released (E_initial-E_final) when an additional electron is attached to a neutral atom or molecule.

 

[abcc]

First EA is negative, not positive.  I don't trust Wikipedia.

if EA is -ive,
EGE also is -ive....
then why EA=-EGE

[abcc]

You should trust the IUPAC gold book then 

http://goldbook.iupac.org/E01977.html

THX FOR the reference

[english]

First EA is negative, not positive.  I don't trust Wikipedia.

if EA is -ive,
EGE also is -ive....
then why EA=-EGE

The 1st Electron Affinity of an element is the enthalpy change when 1 mole of gaseous atoms of that element each gain an electron to form gaseous ions each with a single negative charge.  Often exothermic as the negative electron is attracted to positive nucleus.

Maybe that will help.

[abcc]

First EA is negative, not positive.  I don't trust Wikipedia.

if EA is -ive,
EGE also is -ive....
then why EA=-EGE

The 1st Electron Affinity of an element is the enthalpy change when 1 mole of gaseous atoms of that element each gain an electron to form gaseous ions each with a single negative charge.  Often exothermic as the negative electron is attracted to positive nucleus.

Maybe that will help.

sooooo
EA is -ive as it is exothemic
then that means EA = EGE 
BUT SOMEONE said EA = - EGE

[english]

No!

EGE and EA are the same thing.  You don't say that because EA is negative, and EGE is negative, then EA = EGE.

EA = -EGE

or

EA = -kJ/mol

[abcc]

No!

EGE and EA are the same thing.  You don't say that because EA is negative, and EGE is negative, then EA = EGE.

EA = -EGE

or

EA = -kJ/mol

but if they are the same,
why do they have different 'sign'
-ive and + ive have different meanings respectively.
give an example: if EA= -165, then EGE = +165( since EA= - EGE)
they have same magnitude and meaning
but - ive means energy realeased to surrounding; +ive means energy absorbed .

[maakii]

You should trust the IUPAC gold book then 

http://goldbook.iupac.org/E01977.html

Yes, it says it is negative as well:

The equivalent more common definition is the energy released (E_initial-E_final) when an additional electron is attached to a neutral atom or molecule.

 

The E_initial is higher than E_final if energy is released when an additional e- is attached to a neutral atom/molecule, so it should be positive.

[abcc]

i am still confuseddddd