Properties of Solutions

CA Standards Students know the definitions of solute and solvent. Students know how to describe the dissolving process at the molecular level by using the concept of random molecular motion. Students know temperature, pressure, and surface area affect the dissolving process.

Solutions are homogeneous mixtures

Solute A solute is the dissolved substance in a solution. Salt in salt water Sugar in soda drinks Carbon dioxide in soda drinks Standard 6a ·Solid in Solid-Liquid mixtures ·The lesser amounts in liquid-liquid mixtures ·gas in gas-liquid mixtures

A solvent is the dissolving medium in a solution. Solvent Water in salt water Water in soda Standard 6a ·Liquid in Solid-Liquid mixtures ·The larger amounts in liquid-liquid mixtures ·Liquid in gas-liquid mixtures Water is the universal solvent!!!

“The Solution Process” Standard 6b Caused by the random molecular motion of the solvent What causes solute and solvent to become a solution?

“Factors that Affect the Solution Process” Temperature Agitation (stirring) Surface Area Pressure ( in gas and liquids) Standard 6c

Solubility ·the ability of substance to dissolve ·amount of solute that can dissolve in 100g of water

Solubility Trends Solids tend to dissolve best when: · Heated · Stirred · Ground into small particles Gases tend to dissolve best when: · The solution is cold · Pressure is high

Solubility Chart

“Like Dissolves Like” Fats Benzene Steroids Hexane Waxes Toluene Polar and ionic solutes dissolve best in polar solvents Nonpolar solutes dissolve best in nonpolar solvents Inorganic Salts Water Sugars Small alcohols Acetic acid

Homework: Create "Thinking Maps" for the Lecture and use that to write a short summary of the Lecture