1. Chapter 6: Sports Drink

2. Introductory Activity
What do you think are the benefits of drinking a sports drink while exercising rather than plain water?
How are your ideas influenced by the marketing strategies of the companies that sell these drinks?

3. 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

4. Sports Drinks Properties Solution Concentrations Electrolytes pH
Is a
Properties
Differ from pure liquids in
Solution
How much solute is in it?
With
Concentrations
Electrolytes
Some affect
Can be determined by
that need to all dissolve when mixed together pH
Solubility
Titrations

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

6. Dissolving substances
Substances are dissolved by a process called hydration
The solvent and solute need to break intermolecular forces within themselves
New intermolecular forces are formed between the solvent and solute
The solvent “carries off” the solute particles

7. Dissolving Ionic Compounds+ - O H - +
Ionic compound
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 between the ions, the water carries away the ion. + - + - + -

8. 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. + - + - + - + -

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

10. 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.

11. 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.
- +
- +
- +

12. Dissolving Covalent Compounds
Solvent, water (polar) + -
- +
Solute, sugar (polar)
- +
However, the polar covalent molecules themselves do not split into charged ions—the solute molecule stays together and just separates from other solute molecules.

13. Non-electrolytes
When molecules separate from other molecules (breaking intermolecular forces), but free-floating charges are not produced from breaking intramolecular forces, the solution cannot conduct electricity.
These are called non-electrolytes

14. Types of Electrolytes Strong Electrolytes Weak Electrolytes
Non-Electrolytes
Ionic compounds
Ionic Compounds
Covalent Compounds
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

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

16. 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

17. 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

18. Types of Solutions Unsaturated Saturated Super-Saturated
More solute can be dissolved
No more solute can be dissolved—it’s “full”
Has more solute than would make a saturated solution dissolved
In general, the higher the temperature of a solution, more solid can be dissolved.