How can standard enthelpy values be negative?

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Certain aqueous ions have negative values for SO, such as Ca2+ with -55.2 J/(K*mol); how is this possible when dissolution is usually an increase in entropy?

Also, all pure elements seem to have positive standard entropy value; why is this the case?

Thank you.
 
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Enthalpy or entropy?

Aceix..
 
Oh jeez, I'm so sorry. I meant to say entropy. My bad.
 
Conservation said:
how is this possible when dissolution is usually an increase in entropy?
Start dropping solvent dipoles into an electrical potential well. There's more going on than just entropy of mixing.
 
So is the dipole interaction between the solute and the solvent great enough that dissolution will result in an overall decrease in entropy despite the entropy of mixing?
 
Makes sense. Thank you.
Also, could you answer my other question about elements always having a positive standard enthalpy?
 
Conservation said:
elements always having a positive standard enthalpy?
Enthalpy? Again, you mean "entropy?" It's the integral of Cp/T from absolute zero to 298 K (or whatever T for the table).
 
I really have to stop using the wrong term. I'm so sorry-the suggested threads about enthalpy at the bottom were throwing me off. :(
Okay, I think I see the integral idea now. Your explanation and this site (http://www.science.uwaterloo.ca/~cchieh/cact/applychem/entropy.html) was really helpful.

Thank you.