solutions

2. A solution is a
mixture of 2 or more
substances in a single
phase.
One constituent is
usually regarded as the
and the
others as .

3. Solutions are
homogeneous
mixtures of two or
more pure
substances.
In a solution, the
solute is dispersed
uniformly throughout
the solvent.

4. • SOLUTE – the part of a
solution that is being
dissolved
(usually the lesser amount)
• SOLVENT – the part of a
solution that dissolves
the solute
(usually the greater amount)
ACTIVITY 2.1
IDENTIFYING COMPONENTS OF SOLUTIONS
Solution Solute Solvent
Air in balloon
Ammonia water
Rubbing
alcohol (70%)
Rubbing
alcohol (40%)
Tincture of
Iodine
Sea water
O2 N2
NH3 H2O
H2O Isopropyl alcohol
H2O
Ethyl alcohol
Iodine Alcohol
Salt H2O

5. Identify the solute and solvent in each of the
following solutions.
 1.0 g of sugar dissolved in 100 g of water.
 50 mL of water mixed with 20 mL isopropyl alcohol
 A tincture of Iodine is prepared with 0.10 g I2 and 10.0 mL of
ethyl alcohol.
 40 % ethanol a rubbing alcohol.
 Sugar is the smaller quantity that is dissolving. Therefore it the solute and water is
the solvent.
 Since both water and isopropyl alcohol are liquids, the one smaller volume, is the
solute and water is the solvent.
 Iodine is the solute and ethyl alcohol is the solvent.
 Ethanol is the solvent and water is the solute.

6. Identify the solute and solvent in each of the
following solutions.
 10 g NaCl and 100 g of water.
 50 mL ethanol and 10 mL H2O
 2.0 L oxygen and 8.0 L nitrogen.
100 g silver and 40 g mercury.
 100 mL H2O and 5.0 g sugar

7.  Gas
 Liquid
 Solid

8. SOLUTION SOLUTE SOLVENT EXAMPLE
Gas in a
gas
Gas in a
liquid
Liquid in a
liquid
Solid in a
liquid
Liquid in a
solid
Solid in a
solid
Air
Oxygen Nitrogen
Soda water
CO2 H2O
Vinegar
Acetic acid H2O
Sugar syrup
Sugar H2O
Dental
amalgam
Ag
Hg
Brass or
Steel
Zinc Copper
Carbon Iron

11. Solutions are
homogeneous
mixtures of two or
more pure
substances.
In a solution, the
solute is dispersed
uniformly throughout
the solvent.

12. 1. Solvent molecules attracted to surface ions.
2. Each ion is surrounded by solvent molecules.
3. Enthalpy (DH) changes with each interaction
broken or formed.
Ionic solid dissolving in water

13. The ions are
solvated
(surrounded by solvent).
If the solvent is
water, the ions are
hydrated.
The intermolecular
forces.

14. solvation is an
interaction of a
solute with the
solvent, which
leads to
stabilization of
the solute in the
solution.

15. Dilute
small amount of
solute dispersed
in the solvent
Concentrated
large amount of
solute is dissolved
in the solvent

16. Hypotonic
(lower solute
concentration) to
the solution
Hypertonic
(higher solute
concentration) to
the solution

17. Isotonic
solutions are equal
in their solute
concentrations.
We say that they
are isotonic to
each other.

18. How does a solid
dissolve into a
liquid?
What ‘drives’ the
dissolution process?
What are the
energetics of
dissolution?

19. • is the process by
which a solid,
liquid or gas
forms a solution
in a solvent.

20. • In solids this can be
explained as the
breakdown of the
crystal lattice into
individual ions, atoms
or molecules and their
transport into the
solvent.

21. • For liquids and
gases, the
molecules must be
compatible with
those of the solvent
for a solution to
form.

22. • Dissolution is a physical change—you can get back
the original solute by evaporating the solvent.
• If you can’t, the substance didn’t dissolve, it reacted.
Ni(s) + HCl (aq) NiCl2(aq) + H2(g) NiCl2(s)
dry

24. •refers to the maximum
amount of solute, expressed
in grams, that can be
dissolved in 100 g of water
at a specific temperature &
pressure.

25. Soluble
a substance that
dissolves in a solvent
Insoluble
a substance that
does not dissolve in
a solvent (sand is
insoluble in water)

26. SUBSTANCES KEROSENE OIL
ETHYL
ALCOHOL WATER
Sugar
Salt
Detergent
Powdered
chalk
Powdered
charcoal
Sulfur
powder
CuSO4
KMnO4

27. Immiscible
Two liquids that are
insoluble
(Oil & Vinegar)
Miscible
Two liquids that are
soluble in each other
(Alcohol & Water)
SOLVENT WATER KEROSENE ACETONE ALCOHOL
Oil

28. Saturated solution
Solvent holds as much
solute as is possible at
that temperature.
Undissolved solid
remains in flask.
Dissolved solute is in
dynamic equilibrium
with solid solute
particles.

29. Unsaturated Solution
Less than the
maximum amount
of solute for that
temperature is
dissolved in the
solvent.
No solid remains in
flask.

30. Supersaturated
Solvent holds more solute than is normally possible at that
temperature.
These solutions are unstable; crystallization can often be
stimulated by adding a “seed crystal” or scratching the side
of the flask.

32. • Chemists use the
axiom
• “like dissolves like”
Polar substances
tend to dissolve in
polar solvents.
Nonpolar substances
tend to dissolve in
nonpolar solvents.

33. SOLVENT NaCl C12H22O11 C10H8 I2
Water
SOLVENT WATER KEROSENE ACETONE ALCOHOL
Oil

34. Generally, the
solubility of
solid solutes in
liquid solvents
increases with
increasing
temperature.

35. SOLUTE COLD
WATER
HOT
WATER
TIME TO
DISSOLVE
Salt
Sugar
KNO3

36. The opposite is true
of gases.
• Higher temperature
drives gases out of
solution.
Carbonated soft
drinks are more
“bubbly” if stored in
the refrigerator.
Warm lakes have less
O2 dissolved in them
than cool lakes.

37.  The larger the molecules of the solute are, the larger is their molecular
weight and their size.
 It is more difficult it is for solvent molecules to surround bigger
molecules.
 If all of the above mentioned factors all excluded, a general rule can be
found that larger particles are generally less soluble.
 If the pressure, and temperature are the same than out of two solutes of
the same polarity, the one with smaller particles is usually more soluble.

38. SOLVENT REFINED SALT ROCK SALT
Water
SOLVENT REFINED
KNO3
KNO3
CRYSTALS
Water

39.  Stirring only increases the
speed of the process - it
increases the movement of
the solvent that exposes
solute , thus enabling
solubility.
 As molecules in liquid
substances are in constant
move, the process would
take place anyway, but it
would take more time.

40. SOLUTE SET-UP W/
STIRRING
UNDISTURBED
SET-UP
TIME TO
DISSOLVE
CuSO4
KNO3

41. The stronger the
intermolecular
attractions
between solute
and solvent, the
more likely the
solute will
dissolve.
Example: ethanol in water
Ethanol = CH3CH2OH
Intermolecular forces = H-bonds; dipole-
dipole; dispersion
Ions in water also have ion-dipole forces.

42. Glucose
(which has hydrogen bonding)
is very soluble in
water.
Cyclohexane
(which only has dispersion forces)
is not water-
soluble.

43. • Vitamin A is soluble in nonpolar compounds
(like fats).
• Vitamin C is soluble in water.

45. • In general, the
solubility of gases in
water increases with
increasing mass.
Why?
• Larger molecules
have stronger
dispersion forces.

46. • The solubility of
liquids and solids
does not change
appreciably with
pressure.
• But, the solubility of
a gas in a liquid is
directly proportional
to its pressure.
Increasing
pressure
above
solution
forces
more gas
to
dissolve.

47. States that:

48. Sg = kPg
Where:
• Sg is the solubility of the
gas;
• k is the Henry’s law
constant for that gas in
that solvent;
• Pg is the partial pressure
of the gas above the
liquid.