DO NOW: (on back of HW) What is a solute? What is a solvent? If temperature is increased, does solubility increase or decrease? If agitation is increased, does solubility increase or decrease? If surface area is decreased, does solubility increase or decrease? If pressure increases, does solubility increase or decrease?

Lab Friday! Don’t forget your jar! (Sugar too!)

Unit: Acids, Bases, and Solutions Notes Unit: Acids, Bases, and Solutions Introduction to Solutions

After today you will be able to… Explain the differences between the three different types of solutions Describe how to make a supersaturated solution Describe how to increase the rate of dissolving

A solution is a homogeneous mixture A solution is a homogeneous mixture. The components are not chemically combined and retain their original properties. Example: Sugar water – still tastes sweet

Solutions A solution is made up of a solute and solvent. Solute: a dissolved substance Solvent: the most abundant component of a solution, what does the dissolving

Water is called the “universal solvent” because it has the ability to dissolve so many substances.

Solutions Recall, aqueous is a solution where water is the solvent. Example: NaCl(aq) Na+ + Cl-

Solubility  The maximum amount of solute dissolved in a particular solvent at a specific temperature. Saturated: No more solute can dissolve Unsaturated: More solute can dissolve Supersaturated: More solute is dissolved than theoretically possible

To make a supersaturated solution: Add more solute than solubility allows Heat the solution up Slowly cool it down This is a temporary and unstable state for a solution!

Factors that affect solubility: Temperature: most solid substances have higher solubility as temperature increases All gas solutes have lower solubility as temperature increases Pressure: only affects gas solutes All gas solutes have higher solubility as pressure increases

Solubility Curves For Solid Solutes: For Gas Solutes:

Rate of dissolving: How fast a solute dissolves in a solvent – not to be confused with how much.

Rate can be increased by: Increasing temperature- There is more kinetic energy available to meet the activation energy (energy available for dissolving) Stirring- Increases the interaction between solute and solvent Powdering- Increase surface area of the solute which increases the interaction between solute and solvent

Liquid-Liquid Solutions Miscible: two liquids which uniformly mix together (ex: milk and water) Immiscible: two liquids which will not mix, forms two layers (ex: oil and water) Non-polar + non-polar = miscible Polar + Polar = miscible Non-polar + Polar = immiscible As a general rule: “Like dissolves like”

Concentration Indicates the amount of solute dissolved in a given quantity of solvent. Dilute: a small amount of solute Concentrated: a large amount of solute

Questions? Begin WS!