HOW does temperature affect solubility?

Question

I already know that the heat affects solubility but HOW and WHY does it affect solubility?

Answer 1

How about a simple "hand-waving" explanation?  We will consider the solubility of a solid salt in water where the solubility increases as the temperature increases.

A substance dissolves because the force of "hydration" - the attraction of water molecules - is greater than the force that hold the particles in some form of lattice.  The regular arrangement of atoms is disrupted and the solid dissolves.  As the temperature increases, the water molecules move around more, causing more disruption of the lattice, with a greater force.  This allows for more the solid to be dissolved in water, which is an increase in the solubility.

Answer 2

As the temperature of a liquid increases, the solubilities of gases in that liquid decrease. We can use the Second Law of Thermodynamics to explain why. Heating a solution of a gas enables the particles of gas to move more freely between the solution and the gas phase. The Second Law predicts that they will shift to the more disordered, more highly dispersed, and therefore, more probably gas state.

In a similar way, we can explain why the substances that are solids at room temperature and pressure tend to become more soluble when the temperature rises. Heating a solution of a solid makes it easier for the particles of solid to move between the solution and the solid phase. The Second Law predicts that they will shift to the more disordered, more highly dispersed, and therefore, more probably solution state.

Answer 3

An increase in temperature does not always increase the solubility of a substance.

For most solids, the solubility increases with increasing temperature. (Note: A few solids are less soluble in solutions at higher temperatures) This is because in dissolution, energy, in the form of heat, is required to break the bonds joining the molecules in the solid together. Therefore, if the temperature is higher, heat energy is higher, the rate of bond-breaking is faster, the rate of dissolution is faster.

For exothermic reactions,  wherein heat is released upon formation of the product, an increase in temperature decrease in the solubility. Take a look at this example.

AB ---> A+ + B- (+10 J)

Upon dissolution of AB, 10 J (heat energy) is released. Therefore, the addition of more heat (increasing temperature) inhibits the dissolution since excess heat is already being produced by the reaction (Le Chatelier's Principle).

The opposite happens with endothermic reactions where heat is required to form the product/s.

AB + 10 J ---> A+ + B-

An increase in temp shifts the equilibrium to the right (forward reaction); therefore, the dissolution is faster.

For all gases, solubility decreases with increasing temperature.

This is because an increase in temperature causes an increase in kinetic energy. The higher kinetic energy enables the gas molecules to move more freely between the solution and the gas phase. The Second Law of Thermodynamics predicts that the molecules will shift to the more disordered and more highly dispersed state - the gas state.

Answer 4

heat makes things more solubule....has something to do wit tha speed and diffusion of particles, not too sure on specifics

Answer 5

Heat is requiered to break the bonds holding molecules together. solubility is depandant on temperature.