Verified answer

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

dH reaction = dHf products - dHf reactants

dH rxn = [dHf Na+(aq) & dHf Cl- (aq)] - dHf NaCl(s)

dH rxn = [ -240.1 & -167.2] - (-410.9)

d Hrxn = +3.6 kJ/mol

sorry dH = "+" , & so is not favorable by dH

we know that it does dissolve & dissociate easily...

so dG must be = a "-"

and the only way that dG = "-"...... must be that dS is favorable

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

dS reaction = S products - S reactants

dS rxn = [S Na+(aq) & S Cl- (aq)] - S NaCl(s)

dS rxn = [ 59 & 56.5] - (72.33)

d Srxn = +43.17 joules /mol ... or 0.04317 kJ

well dS = "+" 's are favorable

lets go for the dG @ 25 Cesius, 298Kelvin:

dG = dH - TdS

dG = 3.6 kJ -(298K)(43.17 kJ)

dG = 3.6 kJ - 12.865 kJ

dG = - 9.26 kJ

so because the dG is "-"

and because the dS is "+"

this reaction is favorable

but with no thanks to a "+" dH which is unfavorable