1. Chapter 7A- Solutions p

2. Properties of solutions
Solutions are homogeneous mixtures of substances in the same physical state
Contain atoms, ions, or molecules of one substance spread uniformly throughout a second substance.
Characteristics of liquid solutions:
Solutions are clear and do not disperse light.
Can have a color
Will not settle on standing
Will pass through a filter

3. Components of a solution
SOLUTE: substance being dissolved
present in a smaller amount
SOLVENT: substance doing the dissolving
Present in a greater amount

4. Factors that Affect Solubility
Solubility = how much of a solute will dissolve in a certain amount of solvent at a particular temperature
Temperate
Pressure (ONLY FOR GASES)
Nature of solute/solvent

5. Temperature TABLE G SOLIDS GASES
As temperature increases, solubility increases
GASES
As temperature increases, solubility decreases

6. pressure Only effects gases!
As pressure increases, solubility increases

7. Nature of Solute/Solvent
“Like dissolves like.”
Non-polar solute dissolves in non-polar solvent
Polar solute dissolves in polar solvent
This is why certain things won’t dissolve in water.
Water is ____.

8. Solubility Curves (Table G)
Table G demonstrates the relationship between grams of solute that can be dissolved as temperature increases.
Solids – the positive slope. Increasing lines.
Gases- the negative slopes. Decreasing lines.
SO2, HCl, NH3

9. Solubility UNSATURATED
A solution that holds less solute than the maximum it can hold
BELOW the solubility line
Dilute solution
SATURATED
A solution that contains the maximum amount of solute that will dissolve at a specific temperature
ON the line
SUPERSATURATED
A solution that contains more solute than is present in a saturated solution
ABOVE the line
Concentrated solution

11. Examples
A solution contains 35g of KNO3 dissolved in 100g of water at 40oC. How much more KNO3 would have to be added to make a saturated solution?
A solution containing 90g of KNO3 per grams of H2O at 50oC is considered to be (concentrated/dilute) and (supersaturated/saturated/unsaturated).
A solution containing 55g of NH4Cl in 100g of water is saturated at a temperature of what?

12. Table G is based on 100g of water
If there is a question that asks you to find the solubility in 200 g of water: Multiply answer by 2.
If there is a question that asks you to find the solubility in 300 g of water: Multiply answer by 3.
If there is a question that asks you to find the solubility in 50 g of water: Divide answer by 2.

13. Examples
What is the maximum number of grams of KCl that will dissolve in 200g of water at 50oC to produce a saturated solution?
What is the total number of grams of potassium chloride needed to saturate exactly 300g of water at 10oC?
How many grams of KNO3 are needed to saturate 50. grams of water at 70oC?

14. Solutions and Precipitate
When a solute comes out of solution, It is called a precipitate
If it is a gas, it will escape out the top
Such as CO2 leaving a soda bottle
If it is a solid, it will settle to the bottom
Such as too much sugar in your tea
100g of water is saturated with NH4CL at 50oC. If the temperature is lowered to 10oC, what is the total amount of NH4Cl that will precipitate?

15. Solubility Tables- Table F
A solution is SOLUBLE when it dissolves completely
A solution is INSOLUBLE when it does not dissolve completely and forms a precipitate
Based on Table F

17. Examples: Which of these salts is LEAST soluble in water?
PbCl2 C. FeCl2
LiCl D. RbCl
Which compound is the MOST soluble?
Silver iodide C. Silver Bromide
Silver chloride D. Silver Acetate
Which compound is the LEAST soluble?
Ca(OH)2 C. LiOH
Ba(OH)2 D. Sr(OH)2

18. Open your workbooks to p. 120-121 (1-12)4 2 3 2 1 3

19. Now, p. 123 (13-23) 2
2 or 4 H h F f