slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
CHAPTER 15 PowerPoint Presentation
Download Presentation
CHAPTER 15

Loading in 2 Seconds...

play fullscreen
1 / 40

CHAPTER 15 - PowerPoint PPT Presentation


  • 168 Views
  • Uploaded on

CHAPTER 15. Solutions. Solute. A solute is the dissolved substance in a solution. Salt in salt water. Sugar in soda drinks. Carbon dioxide in soda drinks. Solvent. A solvent is the dissolving medium in a solution. Water in salt water. Water in soda. Concentrated vs. Dilute.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'CHAPTER 15' - raven-weaver


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

CHAPTER 15

Solutions

slide2

Solute

A solute is the dissolved substance in a solution.

Salt in salt water

Sugar in soda drinks

Carbon dioxide in soda drinks

Solvent

A solvent is the dissolving medium in a solution.

Water in salt water

Water in soda

slide4

Saturation of Solutions

  • A solution that contains the maximum amount of solute that may be dissolved under existing conditions is saturated.
  • A solution that contains less solute than a saturated solution under existing conditions is unsaturated.
  • A solution that contains more dissolved solute than a saturated solution under the same conditions is supersaturated.
solubility rules

Solubility Rules

Reference Tables

solubility values
Solubility Values
  • Solubility of a substance is the amount of that substance required to form a saturated solution with a specific amount of solvent at a specified temperature
  • The rate at which a substance dissolves does not alter the substances solubility
factors that affect solubility
Factors that Affect Solubility
  • Temperature
    • Solubility of solids increases with temperature
    • Solubility of gases decreases with temperature
  • Pressure
    • has no real effect on the solubility of liquids and solids in liquid solvents
    • Increasing pressure increases the solubility of gases in liquids
solubility curves
Solubility Curves
  • Each line represents a solute
  • Higher curves mean that the solute is more soluble, lower curves are less soluble
  • ABOVE the curve is SUPERsaturated, on the curve is saturated, and UNDER the curve is UNsaturated
slide11

Solubility Trends

  • The solubility of MOST solids increases with temperature.
  • The rate at which solids dissolve increases with increasing surface area of the solid.
  • The solubility of gases decreases with increases in temperature.
  • The solubility of gases increases with the pressure above the solution.
slide12

Therefore…

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
problem 18
Problem 18

A physical change occurs when

  • A a peach spoils
  • B a bracelet turns your wrist green
  • C a copper bowl tarnishes
  • D a glue gun melts a glue stick
problem 19
Problem 19

What substance has a melting point of -94°C and a boiling point of 65°C?

  • a. Ethanol
  • b. Chlorine
  • c. Hexane
  • d. Methanol
problem 20
Problem 20

22.4 liters of a gas has a mass of 36.5 grams. What is the identity of the gas?

  • a. Chlorine
  • b. Hydrogen chloride
  • c. Nitrogen
  • d. Hydrogen
slide19

Heat of Solution

  • The Heat of Solution is the amount of heat energy absorbed (endothermic) or released (exothermic) when a specific amount of solute dissolves in a solvent.
    • Endothermic: absorbs heat so it feels cool
    • Exothermic: releases heat so it feels hot
slide20

Molarity

The concentration of a solution measured in moles of solute per liter of solution.

mol of solute= M

L of solution

example
Example

What is the molarity of 2.5 mol KCl in 1.0L solution?

M= mol

L

M= 2.5mol

1L

M= 2.5M

example 2
Example 2

What is the molarity of 0.96g MgCl2 in 500mL of solution?

M= mol

L

0.96g MgCl2 1mol MgCl2 = .01 mol MgCl2

95g MgCl2

M= .01 mol MgCl2

.500L

M= .02M

example1
Example

How many moles of solute are contained in 15.25mL of a 2.1M solution of CaCl2?

M = mol

L

# of mol = molarity x L of solution

# of mol = 2.1M (.01525L)

# of mol = .032 mol CaCl2

practice 1

Practice 1

What is the molarity of 1.35 mol H2SO4 in 245mL solution?

M= 5.51M

practice 2

Practice 2

What is the molarity 9.33g Na2S in 450 mL solution?

M= 0.27M

practice 3

Practice 3

How many moles of solute are contained in 125mL of a 0.050M solution of Ba(OH)2?

.00625mol

practice 4

Practice 4

How many grams of solute are contained in 64.3mL of a 0.0238M solution of KOH?

.0859g

practice 5

Practice 5

How many grams of solute are contained in 142mL of a 1.4M solution of K2SO4?

34.6g

dilutions
Dilutions
  • Because the # of moles of solute does not change during a dilution

Moles of solute in the stock solution = moles of solute after dilution

M1V1=M2V2

M1V1 is the molarity and volume of the stock solution and M2V2 is the molarity and volume of the diluted solution

example2
Example
  • How many milliliters of 2.55M NaOH is needed to make 125ml 0.75M NaOH?

M1V1 = M2V2

V1= M2V2

M1

V1=(.75)(125)

2.55

V1= 36.76L

practice 11

Practice 1

How would you prepare 500mL of 3 M HCl using 6 M HCl from the stockroom?

250mL

practice 21

Practice 2

How much 12 M HCl must be used to prepare 500 ml of a 1 M HCl solution?

41.67mL

homework

Homework

Molarity and Dilution Problems

problem 21
Problem 21
  • Which of the following substances best illustrates polar covalent bonding?
    • a. HCl
    • b. NaBr
    • c. CsF
    • d. Cl2
problem 22
Problem 22
  • The methane, CH4, gas molecule exhibits what type of geometric shape?
    • a. trigonal planar
    • b. tetrahedral
    • c. bent or V-shaped
    • d. trigonal pyramidal
problem 23
Problem 23
  • Which substance would have London dispersion forces as the main type of intermolecular forces of attraction?
    • a. H2O
    • b. F2
    • c. HCl
    • d. NaCl
problem 24
Problem 24
  • Which of the following compounds is an exception to the octet rule?
    • a.BH3
    • b.CH4
    • c.NH3
    • d.H2O