Concentration and Solubility 8.2 TEACHER 8.2

What does concentration of a solution mean? Concentration of a solution means - the amount (quantity) of solute that is dissolved in a certain amount of solvent. Example: For a solution of salt water you would ask, “how much salt is dissolved in the water?” The more salt, the more concentrated the salt water solution.

Two ways t o describe concentration 1.Qualitatively: 2.Quantitatively:

Saturated Solution Forms when no more solute will dissolve in a specific amount of solvent at certain temperature..\Animations Unit 3\soluble-salts_en.jar

Solubility expressed as g/L [ see table page 264] SubstanceState (of solute)Solubility (g/L) Is this Qualitatively or Quantitatively described???? Answer:

Rate of Dissolving… What factors affect the rate of dissolving? 1.Size of the solute 2.Temperature 3.Pressure (for gases) 4.Stirring

Size of Solute The smaller the solute particles, the quicker they will dissolve faster

Temperature The higher the temperature, the faster the solute will dissolve faster

Pressure (solubility of Gases) Gases are more soluble in liquids under higher pressure (see page 267) Opened bottle decreases pressure and “bubbles” come out of solution

Stirring increase the rate of dissolving

Activity: Answers questions: 1 – 3 on page 263 and 1 – 4 on page 267 in your text.

How Does Temperature Affect Solubility? Complete Core Activity 8-2A page 268-9