Download What are three ways to measure the concentration of a solution?

S-142
•
•
•
•
What is a
1. A solution
2. An acid
3. A base
Unit 8 Solutions, Acids, & Bases
SPS6 Students will investigate the properties of solutions
a.
Describe solutions in terms of
-
b.
c.
d.
e.
solute/solvent
Conductivity
Concentration
Observe factors affecting the rate a solute dissolves in a specific solvent
Demonstrate that solubility is related to temperature by constructing a solubility curve
Compare and contrast the components and properties of acids and bases
Determine whether common household substances are acidic, basic, or neutral
8.1 Formation of Solutions
What are two processes that can occur when substances
dissolve?
What are some properties of solutions that differ from those of its
solvent and solutes?
What factors affect the rate of dissolving?
8.1 Formation of Solutions
What are three processes that can occur when substances dissolve?
• Dissolving
– Solution – homogeneous mixture of two or more
substances
– Two components
• Solute – substances whose particles are dissolving
• Solvent – substance in which the solute dissolves
– Can be solids, liquids, or gases
– Most common solutions are dissolved in water
8.1 Formation of Solutions
What are two processes that can occur when substances dissolve?
• Two ways substances dissolve
– Dissociation of Ionic Compounds
• First an ionic compound separates into ions
• Called dissociation
• Positive and negative ions are now attracted to the
polar ends of a water molecules
Salt Dissolving
8.1 Formation of Solutions
What are two processes that can occur when substances dissolve?
• Two ways substances dissolve
– Dispersion of Molecular Compounds
• Dispersion – spreading
• Particles break into small pieces and spread
throughout the solvent
• Small pieces = molecules
8.1 Formation of Solutions
What are some properties of a solution that differ from those of its parts
• Solutions Properties
– Conductivity
• Solutions formed by dissociation have lots of ion
• Ions allow the flow of electricity
– Freezing Point
• Solutions have lower freezing points than either the
solvent or the solute
– Salt and ice
– Boiling Point
• Solutions have higher boiling points than either the
solvent or the solute
– antifreeze
8.1 Formation of Solutions
What factors affect the rate of dissolving?
• Factors Affecting Rates of Dissolving
– Surface area
• Greater are – faster
• Crushed particles have a larger surface area
– Temperature
• Higher temperatures cause more frequent collisions
– Stirring
• Increases the collisions with the surface
S-143
• What are the three ways to increase the rate
at which a solute dissolves?
• What is the difference between
dissociation and dispersion?
8.2 Solubility & Concentration
How are solutions with different amounts of solute described?
What factors determine the solubility of a solute?
What are three ways to measure the concentration of a solution?
8.2 Solubility & Concentration
How are solutions with different amounts of solute described?
•
Solubility
–
–
–
The maximum amount of solute that can
dissolve in a solute
At a specific temperature
For example: 36.0 g of salt will dissolve in 100g
of water at 20oC
8.2 Solubility & Concentration
How are solutions with different amounts of solute described?
•
Solubility
–
–
–
Saturated – as much solute as the solvent can
hold at a given temperature
Unsaturated – less than the maximum amount
of solute
Supersaturated – more than the maximum
•
Solutions are heated, solute dissolved, then they are
cooled off
8.2 Solubility & Concentration
What factors determine the solubility of a solute?
•
Factors Affecting Solubility
–
Polarity – like dissolves like
•
•
–
Temperature
•
•
–
Polar molecules will dissolve polar
Nonpolar will dissolve nonpolar
Most solids become more soluble with an increase
in temperature
Most gases become less soluble
Pressure – increases solubility of gases
8.2 Solubility & Concentration
What are three ways to measure the concentration of a solution?
•
Concentration
–
–
The amount of solute dissolved in a solvent
Percent by volume
volume.of .solute
%V 
x100%
volume.of .solution
–
Might have to calculate volume
of solution (solute + solvent)
8.2 Solubility & Concentration
What are three ways to measure the concentration of a solution?
•
Concentration
–
Percent by Mass
mass.of .solute
%M 
x100%
mass.of .solution
8.2 Solubility & Concentration
What are three ways to measure the concentration of a solution?
•
Concentration
–
–
Molarity
Need to calculate the number of moles first
mol 
–
mass
molar.mass
Then plug into equation
for molarity
moles.solute
M
liters .of .solution
S-144
• 13 g of Iron (III) Acetate, Fe(C2H3O2)3, is
dissolved in 0.325 L of water. What is the
• A. Molar mass of the substance?
• B. Number of moles of the solute?
• C. Molarity of the solution?
S-145
• 15 mL of methanol is dissolved in water to
make 92 mL of solution. What is the
• A. Total volume of the solution?
• B. The percent by mass of the solution?
S-146
• 85 g of copper (I) oxide is dissolved in 415 g
(0.415 L) of water.
• A. What is the total mass of the solution?
• B. What is the percent by mass of the
solution?
• C. What is the molar mass of copper (I)
oxide?
• D. What is the molarity of the solution?
8.3 Properties of Acids & Bases
What are some general properties of
acids and bases?
What are the products of neutralization?
8.3 Properties of Acids & Bases
What are some general properties of acids and bases?
•
Acids
–
Produces H+ ions when dissolved
•
–
Sour
•
•
–
Sometimes written as hydronium (H3O+)
Citrus fruits – citric acid (lemons, limes, oranges)
Vinegar
Reacts with Metals
•
•
Dissolves metals
Single replacement reaction where metal replaces
hydrogen and hydrogen gas is formed
8.3 Properties of Acids & Bases
What are some general properties of acids and bases?
•
Acids
–
Indicator changes
•
•
Substances that change color in the presence of an
acid or base
Turns blue litmus paper pink
8.3 Properties of Acids & Bases
What are some general properties of acids and bases?
•
Bases
–
–
Produce OH- ions in solution
Bitter
•
•
–
Unsweet chocolate
Cough syrup
Dissolves organic substances
•
You – feel slippery
– Skin is dissolving
8.3 Properties of Acids & Bases
What are some general properties of acids and bases?
•
Bases
–
Indicators
•
Changes pink litmus paper blue
8.3 Properties of Acids & Bases
What are the products of neutralization?
•
Neutralization
–
The reaction between an acid and a base
•
•
Produces water and a salt
Salt – negative ion from acid combines with the
positive ion from the base
HA  BOH  BA  H 2O
•
For example
HCl  NaOH  NaCl  H 2O
S-147
• What are four properties of
• A. Acids
• B. Bases
S-148
• Complete the following acid base
neutralization reations
• H2S + KOH 
• Mg(OH)2 + HF 
8.4 Strength of Acids & Bases
How is pH used to describe the concentration
of acids and bases?
How do strong acids and bases differ from
weak acids and bases?
8.4 Strength of Acids & Bases
How is pH used to describe the concentration of acids and bases?
•
The pH scale
–
–
–
–
–
Measures the H+ ion concentration in a
solution
7 is neutral (water)
Acids from less than 7 to 0
Bases from greater than 7 to 14
General pH values
8.4 Strength of Acids & Bases
How do strong acids and bases differ from weak acids and bases?
•
Strong Acids and Bases
–
Acids – completely ionize
•
•
–
Completely fall apart into H+ and ASulfuric Acid, Nitric Acid, Hydrochloric Acid
Bases – completely dissociate
•
•
Completely fall apart into B+ and OHCalcium Hydroxide, Potassium Hydroxide, Sodium
Hydroxide
8.4 Strength of Acids & Bases
How do strong acids and bases differ from weak acids and bases?
•
Weak Acids and Bases
–
Acids – slightly ionize
•
•
–
Only a part of the acid fall apart into H+ and AAcetic Acid (vinegar)
Bases – slightly dissociate
•
•
Only partially fall apart into B+ and
OHAmmonia
8.4 Strength of Acids & Bases
How do strong acids and bases differ from weak acids and bases?
•
Important
–
–
–
Concentration and Strength are different
Concentration – how much is dissolved
Strength – how much of the dissolved
acid/base will fall apart
S-150
• What is the difference between a strong acid
and a weak acid?
• What is the pH range of
– Acids
– Water
– Bases
S-151
Test Day!!
S-152
1. What is the density of a
14.2 g elephant if it has a
volume of 5.7 mL?
2. If the density of a block of rubber was
found to be 9.2 g/cm3, what is the
volume if the mass if 21.7 g?
S-153
• The fastest animal in the world is a
Cheetah. They can run 100 m in 3.21s.
• A. What is the speed of a Cheetah?
• B. How long would
it take a Cheetah to
run a 40m dash?
S-154
What factors does the kinetic energy of an object depend on?
• A 2000 kg cruise missile is flying at 245
m/s. How many joules of kinetic energy
does it have?
S-155
How are work and power related?
• During the worlds strongest man
competition, this man moved a 20,000-N
truck a distance of 12-m in 60-s.
• A. How much work did he do.
• B. How much power did he
generate?
S-156
What determines the frequency of a wave?
• A wave of light has a speed of 300,000,000
m/s. What is the wavelength of a wave
with a frequency of 450,000,000 Hz?
S-159
How do electromagnetic waves differ from one another?
• A. What is the speed of light in a vacuum?
• B. If a light beam has a wavelength of
6.33x1011 m, what is the frequency?
S-160
Students will investigate the properties of electricity and magnetism?
• What are the two types of charges?
• What are the two basic charged particles?
• How does a
charge form?
S-161
What does an electron do to create a
magnetic field?
What is a domain?
What must happen to the domains in a
substance for it to be a magnet?
S-162
What are three types of nuclear radiation?
• Name the three types of
radiation, describe
each is, and what is
protect yourself
nuclear
what
needed to
from them.
S-163
Students classify matter.
• Classify the following
–
–
–
–
Dirty water
Sodium Bicarbonate Solution
Iron (III) Sulfate
Titanium Rod
S-164
How can kinetic theory and forces of attraction be use to explain the
behavior of gases, liquids, and solids?
• Use the kinetic theory to explain the
difference between solids, liquids, and gases.
S-165
• List the atomic number, mass number,
number of protons, neutrons, electrons, and
the name of the following elements.
S-166
• What two characteristics are used to
organize the modern periodic table?
S-167
• Write the correct formula for compounds
formed by the combination of
• A. Silver and Iodine
• B. Boron and Phosphorus
• C. Strontium and Chlorine
S-168
• Write the formula for
– Palladium (IV) Oxide
– Calcium Fluoride
– Cadmium (II) Nitride
Write the name for
- Al2S3
- Rb3P
- CrO3
S-169
• What is the molar mass of
Al2(SO4)3
S-171
1. What is big and red and dingle dangles
from the ceiling?
2. What is the difference between a duck?
S-172
1. What do Santa Claus and a mouse have in
common?
S-173
1. Use the words, defeat, deduct, defense, and
detail in a single sentence.