Chapter 6: Sports Drink
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?
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
Sports Drinks
Is a
Differ from pure
liquids in
Properties
Solution
With
How much
solute is in it?
Concentrations
Electrolytes
Some affect
that need to all
dissolve when
mixed together
Solubility
pH
Can be
determined by
Titrations
Section 6.1—Solutions &
Electrolytes
What are those “electrolytes” they say you’re replacing by drinking sports drinks?
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
Dissolving Ionic Compounds
O
H
H
-
water
+
Ionic compound
+
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.
Dissolving Ionic Compounds
O
H
H
-
water
+
Ionic compound
+
As more ions are “exposed” to
the water after the outer ions
were “carried off”, more ions
can be “carried off” as well.
+
-
+
-
+
-
+
-
Dissolving Ionic Compounds
O
H
H
-
water
+
Ionic compound
+
+
-
These free-floating ions in the
solution allow electricity to be
conducted
-
+
-
-
+
+
-
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.
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.
+
-
+
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.
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
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
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
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
 K+1 + NO3-1
Ca(NO3)2
 Ca+2 + 2 NO3-1
Na2CO3
 2 Na+1 + CO3-2
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
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.