1. Chapter 6: Sports Drink

2. Sports Drinks
This chapter will introduce the chemistry needed to understand how Sports Drinks work
Section 6.1: Solutions & electrolytes
Section 6.2: Concentrations of solutions
Section 6.3: Acidity & pH
Section 6.4: Solubility & precipitates
Section 6.5: Stoichiometry
Section 6.7: Limiting Reactants
Section 6.6: Properties of solutions

3. Section 6.1—Solutions & Electrolytes
What are those “electrolytes” they say you’re replacing by drinking sports drinks?

4. Dissolving substances
Substances are dissolved by a process called hydration when the solvent is water
The solvent and solute need to break intermolecular forces within themselves- This requires ENERGY (ENDOTHERMIC)
New intermolecular forces are formed between the solvent and solute.- This releases ENERGY(EXOTHERMIC)
The solvent “carries off” the solute particles

5. Solution Formation
Endothermic
Exothermic
Endothermic

6. Dissolving Ionic Compounds+ - O H - +
Solute,Ionic compound
Solvent,water
Water molecules are polar and they are attracted to the charges of the ions in an ionic compound. - + -
When the intermolecular forces are stronger between the water and the ion than the intramolecular forces between the ions, the water carries away the ion. + - + - + -

7. Dissolving Ionic Compounds+ - O H - +
Ionic compound
water -
As more ions are “exposed” to the water after the outer ions were “carried off”, more ions can be “carried off” as well. + - + - + - + -

8. Dissolving Ionic Compounds+ - O H - +
Ionic compound
water + -
These free-floating ions in the solution allow electricity to be conducted - + - + - + -

9. Electrolytes
When there are free-floating charges in a solution then it can conduct electricity.
Things that produce free-floating charges when dissolved in water are called electrolytes.

10. Dissolving Covalent Compounds
Solvent, water (polar) + -
- +
Solute, sugar (polar)
Polar covalent molecules are formed in the same way—water forms intermolecular forces with the solute and “carries” the solute particles away.
- +
- +
- +

11. Dissolving Covalent Compounds
Solvent, water (polar) + -
- +
Solute, sugar (polar)
However, the polar covalent molecules stay together and just separates from other solute molecules. NO charged ions form.
- +

12. Non-electrolytes
When molecules separate from other molecules, but free-floating charges are not produced, the solution cannot conduct electricity.
These are called
non-electrolytes

13. Types of Electrolytes Strong Electrolytes Weak Electrolytes
Non-Electrolytes
Soluble
Ionic compounds
Strong Acids & Bases
Insoluble
Ionic Compounds
Weak Acids & Bases
Covalent Compounds except for ACIDS & BASES
Almost all ions are separated when dissolved in water.
Only a few ions are separated when dissolved in water
No molecules separate—ions are not formed
Easily conducts electricity when dissolved in water
Conducts electricity slightly when dissolved in water
Does not conduct electricity at all when dissolved in water

14. Breaking up Electrolytes
Leave polyatomic ions in-tact (including the subscript within the polyatomic ion)
All subscripts not within a polyatomic ion become coefficients
Be sure to include charges on the dissociated ions!
Example:
Break up the following ionic compounds into their ions
KNO3
Ca(NO3)2
Na2CO3

15. Breaking up Electrolytes
Leave polyatomic ions in-tact (including the subscript within the polyatomic ion)
All subscripts not within a polyatomic ion become coefficients
Be sure to include charges on the dissociated ions!
Example:
Break up the following ionic compounds into their ions
KNO3
Ca(NO3)2
Na2CO3
 K+1 + NO3-1
 Ca NO3-1
 2 Na+1 + CO3-2

16. Misconceptions about dissolving
People often describe something that dissolves as having “disappeared”
Before the solute dissolves, it’s in such a large group of particles that we can see it.
After dissolving, the solute particles are still there—they’re just spread out throughout the solution and are in groupings so small that our eyes can’t see them

17. Types of Solutions
A solution is made of two parts:
SOLUTE: the substance that is dissolved; usually in minority
SOLVENT: The substance that does the dissolving, usually in majority
SOLID-LIQUID
LIQUID-SOLID
GAS-LIQUID
Salt Water
Dental Filling (Mercury in Silver)
SODA
(Carbon dioxide gas in water)
When 2 substances dissolve in one another, they are considered SOLUBLE
If they cannot dissolve in one another, they are INSOLUBLE

18. Types of Solutions When 2 liquids dissolve in one another, they are
SOLID-SOLID
LIQUID-LIQUID
GAS-GAS
ALLOYS
(brass, bronze, sterling silver, steel)
Alcohol & water
Acetic acid in water(vinegar)
AIR
(Oxygen in Nitrogen gas)
When 2 liquids dissolve in one another, they are
considered MISCIBLE
If they cannot dissolve in one another, they are IMMISCIBLE.

19. Types of Solutions Unsaturated Saturated Super-Saturated
Has more solute dissolved than a saturated solution has at room temperature
No visual- need some background information
Not full- we can add solute to the solvent & it will dissolve
Visual-no solid on bottom
It’s “Full”- no more solute can be dissolved
Visual- solid can be seen at the bottom

20. Diagrams of Unsaturated,Saturated, & SuperSaturated Solutions

21. Diagrams of Unsaturated vs Saturated Solutions

23. A SUPERSATURATED SOLUTION
A supersaturated solution can be seeded. This is a solution at room temperature that has beyond the maximum amount of solid it can dissolve.

24. A SUPERSATURATED SOLUTION
Crystallization Begins.

25. A SUPERSATURATED SOLUTION
Crystallization Continues.

26. A SUPERSATURATED SOLUTION
A SuperSautrated solution is now saturated. This is also very exothermic!

27. Solubility of a Gas vs Liquid
In general,
the higher the temperature of a solution, more solid can be dissolved.
the higher the temperature of a solution, less gas can dissolve. Thermal Pollution!

28. Solubility of Gas vs Liquiud

29. Henry’s Law
As the pressure above a liquid increases, the solubility of a gas within a liquid will increase

30. Reading a Solubility Curve
Find the data point on the graph of the temperature and solubility of solute in solvent.
If it is below the line, it is UNSATURATED
IF it is on the line, it is SATURATED
If it is above the line, the difference between the point and the line is the extra amount that is sitting at the bottom.

31. Reading a Solubility Curve
Examples
What kind of solution occurs when 40g of KCl is dissolved in 100 g H2O at 60ºC?
What kind of solution occurs when 40g of KCl is dissolved in 100 g H2O at 40ºC?
What is the maximum amount of NaBr that can be dissolved in 100 g H2O at 60ºC?
unsaturated
saturated
120 g

32. Reading a Solubility Curve
Examples
4. What is the maximum amount of KNO3 that can be dissolved at 70ºC?
5. According to the diamond mark, How much of the KNO3 has been added to the water at 70ºC?
6. How much extra KNO3 is sitting at the bottom of the container at this temperature of 70ºC?
140g
160g
20g

33. Factors that Affect the Rate of Hydration
1. Temperature
2. Particle Size
3. Agitation (stirring)

34. Section 6.2—Concentration
How do we indicate how much of the electrolytes are in the drink?

35. Concentration
A measure of the amount of solute in a given amount of solution
Qualitative Description:
Dilute: small amount of solute compared to solvent
Concentrated: large amount of solute compared to solvent
Concentrated
Dilute

36. Concentrated versus Dilute
solvent
solute
Lower concentration
Not as many solute (what’s being dissolved) particles
Higher concentration
More solute (what’s being dissolved) particles

37. Molarity: a quantitiative description of concentration
Molarity (M) is a concentration unit that uses moles of the solute instead of the mass of the solute
2M solution is 2 moles of solute dissolved in 1.0 L of solution
moles
Molarity X
Liters

39. Molarity Example Example:
If you dissolve 5.0 moles of NaCl in mL of water, what is the molarity?

40. Molarity Example 17 M NaCl Example:
If you dissolve 5.0 moles of NaCl in mL of water, what is the molarity?
Remember to change mL to L! mL of water = L
17 M NaCl

41. If you dissolve 12 g of NaCl in 150 mL of water, what is the molarity?
Molarity Example
Example:
If you dissolve 12 g of NaCl in 150 mL of water, what is the molarity?

42. If you dissolve 12 g of NaCl in 150 mL of water, what is the molarity?
Molarity Example
Example:
If you dissolve 12 g of NaCl in 150 mL of water, what is the molarity? Na Cl 1
22.99 g/mole
35.45 g/mole  = +
58.44 g/mole
1 mole NaCl molecules = g
12 g NaCl 1
mole NaCl
= _______ mole NaCl
0.21
58.44
g NaCl
Remember to change mL to L! 150 mL of water = L
1.4 M NaCl

43. Molarity Example Example:
How many grams of CaCl2 would be needed to make 25.0 ml of a 2.5M solution?

44. Molarity Example = 6.9 grams CaCl2 .0625 moles NaCl
How many grams of CaCl2 would be needed to make 25.0 ml of a 2.5M solution? Ca Cl 1 2
40.01 g/mole
35.45 g/mole  =
40.08 g/mole
70.90 g/mole +
g/mole
1 mole CaCl2 = g
.063 mol CaCl2
110.98
g CaCl2
= grams CaCl2
1 mol
CaCl2
Remember to change mL to L! 25 mL of water = L
.0625 moles NaCl

45. How to Make a Solution Make 500.0 ml of a .12 M solution of CoCl22H2O
1st: Convert your moles of solute to grams.
.12 M x .500L = .060 moles solute
.060 moles x g/1mol = g
(10. g)
2nd : Add solute amount to a volumetric flask.
Add 10.0 g cobalt chloride to flask
3rd : Add enough solvent to make the required amount of solution and stir.
In this case, the solvent is ethanol. Add slowly until 500 ml of solution is reached.

46. What Not to Do! Never add the solvent first!

47. Dilution: A technique used to make a dilute solution from a Concentrated Solution
= mol
.10 L
= .050 M I2
= mol
.50 L
= .010 M I2

48. How to Calculate a Dilution
M1V1= M2V2
moles1 = moles2
M1V1 = original (stock) concentration &
volume
M2V2 = new concentration & volume
You do not have to change your volume to liters!
Example:
What is the molarity of a new solution if you diluted ml of 3.0M HCl to ml?

49. Example:. What is the molarity of a new solution if you diluted 100
Example: What is the molarity of a new solution if you diluted ml of 3.0 M HCl to ml?
M1V1= M2V2 (3.0M)(100.0ml) = (X)(250.0 ml) Mml= 250.0ml x ml 250.0ml X= 1.2 M

50. Section 6.3—Acidity, pH
How does concentration of acid affect the pH of a sports drink?

51. Review of Acids – Arrhenius Definition
Acids produce Hydronium ion (H3O+1) in water
Hydronium ion is water + a hydrogen cation H O
water H O +1 H +1

52. Bases – Arrhenius Definition
Bases produce the hydroxide ion in water H O -1
Hydroxide Ion

53. A new of definition of an ACID: According to Bronsted-Lowry
An acid is a hydrogen (proton) donor
The substance that remains after the hydrogen has been donated is called the conjugate base
Example: NH H2O  OH NH4+
acid conjugate base

54. A new of definition of a BASE: According to Bronsted-Lowry
A base is a hydrogen (proton) acceptor
The substance that forms after the hydrogen has been accepted is called the conjugate acid
Example: NH H2O  OH NH4+
base conjugate acid

55. Conjugate Acid-Base Pairs
ACIDS & BASES WILL ALWAYS BE ON THE REACTANT SIDE
CONJUGATE ACIDS & BASES WILL ALWAYS BE ON THE PRODUCT SIDE
Practice Problems: Label the acid & base on the left side of the reaction and the conjugate acid & conjugate base on the right side.
a) HCl H2O  H3O Cl−
______ ______ ______ ______
b) HCO H2O  H2CO OH−
_____ ______ ______ ______
acid
base
C.A.
C.B.
base
acid
C.A.
C.B.

56. Characteristics of Acids & Bases
Produce H3O+1 (hydronium ion) in water
Produce OH-1 (hydroxide ion) in water
Tastes sour
Tastes Bitter
React with active metals to form hydrogen gas
Feels slippery
Turns blue litmus red
Turns clear in phenolphthalien
Turns red litmus blue
Turns pink in phenlphthalien
React with bases to form salt and water (neutralization reaction)
React with acids to form salt and water (neutralization reaction)
Both are considered electrolytes

57. Strength versus Concentration

58. Strong versus Weak Acids
How many hydronium ion – anion pairs can you find? - + - 3 +
How many intact acid molecules can you find? + - 1
In a Strong acid
Most of the acid molecules have donated the H+1 to water

59. Strong versus Weak Acids+
How many hydronium ion – anion pairs can you find? 1
How many intact acid molecules can you find? - 3
In a Weak acid
Only a few of the acid molecules have donated the H+1 to water

60. Acids and Bases as Electrolytes
Acids and bases dissociate into ions in water
Free-floating ions in water conduct electricity
Acids & Bases are electrolytes
Strong acids and bases are strong electrolytes
Weak acids and bases are weak electrolytes

61. Calculating pH

62. pH Scale Is a measure the acidity of a sample 14 7
less acidic, more basic 14
Highly acidic
Very basic (not acidic)
neutral 7
more acidic, less basic
Acids have a pH that are less than 7.0
Bases have pH values that are more than 7.0
Neutral is considered a pH of 7.0

63. Calculating pH pH scale – Logarithmic scale of the acidity
of a solution
pH has no units
The pH scale uses base “10”
The formula for calculating pH
The formula for calculating hydronium ion concentration
[ ] = concentration in Molarity

64. The “-” in the pH equation
Because pH is the negative log of concentration of hydronium, as concentration increases, the pH goes down.
The lowest pH is the highest concentration of hydronium ion

65. What does a “log” scale really mean?
Every change of 1 in pH shows a change of 10x in concentration of hydronium pH 4 3 2 1
Level of acidity increases
1000x more acidic
100x more acidic
10x more acidic

66. Example The pH of a solution changes from a pH of 5 to a pH of 3.
Did it increase or decrease in hydrogen ion concentration?
By what factor did it change?

67. Example 2 :Calculating pH
Find the pH if the concentration of [H3O+1] is 1.0x 10-8 M

68. An example of calculating pH
Find the pH if the concentration of [H3O+1] is 1.0 x 10-8 M
pH = 8.00

69. Example 3; Calculating hydronium concentration ([H3O+1])
Find the [H3O+1] if the pH is 5.0

70. An example of calculating hydronium
Find the [H3O+1] if the pH is 5.0
H3O+1 = 1 x 10-5 M

71. Auto-ionization of Water
Water molecules collide spontaneously and will split into ions. This is called auto-ionization
H2O + H2O  H3O+1 + OH-1
At 25°C the following is true:
[H3O+1] × [OH-1] = 1.0 × M2

72. Hydrogen Ion Concentration Values
If the hydrogen ion concentration is greater than hydroxide ion, the solution is ACIDIC with a pH < 7
[H+] > [OH-] or
[H+] > 1.0 x 10-7 M
If the hydrogen ion concentration is less than hydroxide ion, the solution is BASIC with a pH > 7
[H+] < [OH-] or
[H+] < 1.0 x 10-7 M
If the hydrogen ion concentration is equal to hydroxide ion, the solution is NEUTRAL with a pH = 7
[H+] = [OH-] = 1.0 x 10-7 M

73. Calculating pOH The formula for calculating pOH
The formula for calculating hydroxide ion concentration
To relate pH and pOH
[ ] = concentration in Molarity

74. Find the pOH if the concentration of [OH-1] is 1.0 × 10-5 M
Let’s Practice #1
Example:
Find the pOH if the concentration of [OH-1] is 1.0 × 10-5 M

75. Find the pOH if the concentration of [OH-1] is 1.0 × 10-5 M
Let’s Practice #1
Example:
Find the pOH if the concentration of [OH-1] is 1.0 × 10-5 M
pOH = 5.00

76. Let’s Practice # 2
Example:
Find the pOH if the pH is 4.

77. Let’s Practice #2
Example:
Find the pOH if the pH is 4.
pOH= 10

78. Find the [OH-1] if the [H+] is 1.0 x10-9M
Let’s Practice #3
Example:
Find the [OH-1] if the [H+] is 1.0 x10-9M

79. Let’s Practice #3: 2 ways to do this… 1st way
Example:
Find the [OH-1] if the [H+] is 1.0 x10-9
[OH-] = 1.0 x10-5 M

80. Let’s Practice #3: 2 ways to do this… 2nd way
Example:
Find the [OH-1] if the [H+] is 1.0 x10-9
pH = 9.00
pOH = 14
pOH = 5.00
[OH-] = 1.0 x10-5 M

81. What is the pH if the concentration of [OH-] = 1.0 x 10-7M
Let’s Practice #4
Example:
What is the pH if the concentration of [OH-] = 1.0 x 10-7M

82. What is the pH if the concentration of [OH-] = 1.0 x 10-7
Let’s Practice #4
Example:
What is the pH if the concentration of [OH-] = 1.0 x 10-7
pOH = 7
pH = 7