2. How Solutions Form

3. SC Standards Covered Standard PS-3.5 Explain the effects of temperature, particle size, and agitation on the rate at which a solid dissolves in a liquid.

4. What is Solubility? A substance is soluble in a substance if it will dissolve in that substance. Solubility: The maximum amount of a substance that can dissolve in a given volume at a particular temperature and pressure.

5. What is a Solution? Solution – a mixture that has the same composition, color, density, and taste throughout (homogeneous mixture)

6. Two Parts of a Solution Solute - substance that is dissolved solvent - dissolving medium… substance doing the dissolving

7. Examples of Solutions Gas in gas – air (oxygen in nitrogen) Gas in liquid – Soda (carbon dioxide in water) Liquid in liquid – rubbing alcohol (water in alcohol) Solid in liquid – seawater (salt in water) Solid in solid – sterling silver (copper in silver)

8. Alloys Alloy - solution of metals dissolved in other metals Bronze Brass Sterling silver 10K, 14K, & 18K Gold Stainless steel

9. Water… the Universal Solvent Water is polar: it has oppositely charged ends Ionic Compounds = (+) and (-) ions

10. + end of water attaches to (-) ions of crystal - end of water attaches to (+) ions of crystal Ions pulled away from crystal

11. Ions surrounded by water molecules Continues to happen until all ions separated

13. Rates of Dissolving… What are some ways to make things dissolve faster?

14. Factors that Increase the Rate of Dissolving 1.) Stirring the Solution - solvent particles collide with the surface of the solute more frequently and the dissolving process occurs faster.

15. 2.) Heating the Solvent - speeds up the solvent particles so there are more frequent collisions between solvent and solute

16. 3.) Smaller Solute Particle Size - increases surface area so there are more places the solvent can get to the solute and pull the particles into solution faster

17. What does it mean to be Saturated? Saturated Solution: The maximum mass of solute is dissolved in the solvent at a particular temperature… Saturation is used in crystal formation… such as in making rock candy and in the forming of stalactites and stalagmites in caves.