Solutions

1

• Solutions Solubility
• Factors Affecting Solubility

2

• A solution is the same thing as a homogeneous
  mixture (a mixture with the exact same
  composition throughout).

3
Parts of a Solution

• Solute-the substance that is being dissolved in a
  solution
• Solvent-the substance in a solution that is doing
  the dissolving

4
Parts of a Solution

• Example
• In a saltwater solution (salt dissolved in
  water)
• Salt is the solute
• Water is the solvent

5

• When two liquids are able to dissolve into each
  other, they are called miscible.
• ex) water vinegar
• If not, they are called immiscible.
• ex) water oil

6

• Solubility is the amount of a substance that will
  dissolve into an amount of solvent at a given
  temperature

7

• A solvent (like water, for example) can only hold
  so much of a solute.
• Or in other words, there is a maximum amount of
  solute that any solvent can hold.

8

• Concentration-the amount of solute that is
  dissolved into a solvent
• Concentrated-when a solution has a high
  concentration of solute
• Dilute-when a solution has a low concentration of
  solute

9

• Concentration can be described in terms of weak
  or strong, concentrated or dilute, but
  these are both relative terms and can be
  subjective.

10

• A more objective way to describe concentration is
  molarity we will discuss molarity in more detail
  later this year.

11

• A saturated solution cannot hold any more of a
  solute at a given temperature.
• An unsaturated solution can hold more solute at a
  given temperature.

12

• Sometimes, a solution can hold more of a solute
  than it should theoretically hold. This type of
  solution is called supersaturated.
• A supersaturated solution requires heating and
  stirring.

13
Supersaturated Solution Video
14
Summary Types of Solutions
Unsaturated
Saturated
Super Saturated
Solvent can not hold more solute full
Solvent can hold more solute not full
Solvent holds more solute than normal extra
full
15
Soup Can analogy Think of the solvent as a
can, and the solute as the soup.
Unsaturated
Saturated
Super Saturated
16

• In gases, pressure affects solubility. The
  higher the pressure, the more gas is soluble in a
  solvent.
• ex) carbonated drinks

17

• Generally, a substances solubility increases as
  temperature is increased.
• Why?
• The solvents particles are moving faster and can
  dissolve more solute.

18

• In gases, however, as the temperature increases,
  the solubility of the gas decreases.
• ex) power plants can kill fish because of the
  increased temperature of the water and reduced
  levels of oxygen

19
Effect of temperature on solubility (solubility
chart)
20
Practice Problem 1

• How many grams of KNO3 can 100 grams of water
  hold at 70 oC?
• 120 grams

21
Practice Problem 2

• At what temperature can 100 grams of water hold
  70 grams of KBr?
• 25 oC

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Practice Problem 3

• How many grams of NaNO3 can 75 grams of water
  hold at 55 oC?
• 105 grams of NaNO3 in 100 grams of water
• 105 g/100 g x /75 g
• X (105x75)/100
• X 78.75 g NaNO3

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Practice Problem 4

• What type of solution results when you mix 45 g
  of NH4Cl in 100 g of water at 70 oC?
• Can hold 63 g 45 g lt 63 g solution is
  unsaturated.

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LMS/Chemistry/Lessons/SolubilityOpen and Save
the 2 files titledSolubility Worksheet w/
curve 1213 Solubility Worksheet 1213 Use the
remaining class time to work on these 2
worksheets ELECTRONICALLY.