Help with Chemistry

[Kaitlin]

Hoping for a little help with a problem.I'm given info that CO2's solubility in water falls when temperature rises and the question is to figure out if the enthalpy of solvation of CO2 in water is exothermic or endothermic. Please help!!! but don't answer the whole question I just need pointed in the right direction. So could you give me a clue and I'll try to do the rest.

[NanoMachine]

Le Chatelier's Principle.

[Kaitlin]

Le Chatelier's Principle. If the conditions of a system at equilibrium are changed, the system moves in such a way as to oppose the effects of that change.

CO2 (g) + H20 (l) <=> CO2 (aq)

T rises makes system moves to the left.

This means moving to the left must cool the system. So moving to the right must heat the system. Heating the system means exothermic. Moving to the right is exothermic so disolving the CO2 in water is EXOTHERMIC.

Is that right?

[NanoMachine]

Looks good to me.

[Kaitlin]

Thanks NanoMachine. Here's another problem.

Sodium has electronic structure 2,8,1 and so loses its outermost electron to become a uni-positive cation with the same structure as neon.

Question: Why don't Na+ ions form a gas like neon, whose electronic structure they share.

[Paul Robbins]

Unlike Ne atoms, Na⁺ ions can't exist naturally in isolation. In common salt, for example, each sodium atom gives one electron to a chlorine atom.

In ionic compounds there are very strong electrostatic bonds between the Na⁺ and the Cl^-. The result of these strong bonds is a high melting point ionic solid.