Thermodynamic properties, Chemistry

Thermodynamic properties:

Salts dissolve producing both cations and anions. It means that it is impossible to measure thermodynamic data for individual ion type. The solvation of ions from the gas phase is a thermodynamically favorable exothermic process, which increases the stability of the ions in solution and gives out energy. However, in order for the enthalpy of solution to be exothermic, this enthalpy of solution must be greater than the lattice enthalpy; otherwise the overall reaction is endothermic.

 

136_thermodynamic properties.png

Fig. The conflict in symmetry

between bulk water and water in a

hydration shell.

Qualitative treatment of ionic interaction:

At very low ionic concentration, the solvated cations and anions are so far apart that they do not interact significantly. At higher concentrations the ions are closer together and ion-ion interactions between the cations and anions are important. These are energetic-ally favorable, as the ions tend to cluster around other ions of opposite charge (counter-ions) and avoid ions of like charge (co-ions). This process further decreases the energy of the system and stabilizes the solution. That means although ions move dynamically in solution, on average each cation has as nearest neighbors more anions than cations and each anion more cations than anions. An ionic atmosphere of ion of overall opposite charge therefore surrounds each ion (Fig. 3).

2469_thermodynamic properties1.png

 

Fig. The ionic atmosphere

surrounding a cation (...) and an anion

(---) in solution.

Posted Date: 7/20/2012 4:27:32 AM | Location : United States







Related Discussions:- Thermodynamic properties, Assignment Help, Ask Question on Thermodynamic properties, Get Answer, Expert's Help, Thermodynamic properties Discussions

Write discussion on Thermodynamic properties
Your posts are moderated
Related Questions
Soaps - Oils and fats Soaps are the metallic salts of higher fatty acids like stearic, palmitic, oleic, etc. The potassium and sodium salts are the common soaps that are solubl

Applications of flame photometry: A few common applications of flame photometry are given below. Flame photometry could be used to detect the presence of the elements o


A solution contains an unknown amount of osmium at the µg/g level, or below. Chemically pure osmium (Os) may be separated from the solution, but the chemical yields are variable an

explain why carbon tetra-chloride does not dissolve in water?

Q. Explain about Optical Isomerism? Optical Isomerism: -Two isomers which have almost identical physical and chemical properties like mp. B p. density. Colour etc.. But diffe

name the silicon present compound and their uses

what is the defination of interstitial?

The set of quantum numbers n= 3, l=0, m=0, s= -1/2 belongs to the element: (1) Mg                   (2) Na        (3) Ne                (4) F Ans: Mg