Acids and Bases
Chemistry
Lowell High School 2006-2007
2/20/07 to …
Agenda
 FYI’s
 Reading Report
 Acids/Bases
 Preamble 8
Tuesday, February 20, 2007
FYI
 RLog 16
 Quiz (chap 15)
 QP 16 (1-49 odd)
 Garden Project
(look online)
 RLog 10/14
Tuesday, February 20, 2007
TODAY
2/23 Friday
3/2 Friday
3/5 Monday
3/12 Monday
Reading Log Report
 On your whiteboard, construct a reading
report for chapter 16 (10 min)
 Include 3 bullet points and cite section #
Interconnected
Interesting
Important
Incomprehensible
Tuesday, February 20, 2007
Clarification
Acids/Bases
 Acid = produces hydrogen (donor)
 Base = accepts hydrogen (acceptor)
 Acidity and Basicity are measured
using the pH/pOH scales (range 0-14)
 pH = – log [H+]
pOH = – log [OH-]
 pOH + pH = 14
[H+][OH-] = 1 x 10-14
Tuesday, February 20, 2007
Preamble 8
Determine the pH of 100.0 mL of a
1.00 M HCl solution.
Suppose you double the volume of the
solution by adding water. What is the
new pH? You double the volume once
more with water. What is the new pH? If
you continue to add more water, what is
the maximum pH that can be reached?
Explain your answer.
Tuesday, February 20, 2007
Agenda
 FYI’s
 Acid/Base
Preamble 8
Water’s Equilibrium
Neutralization
 Preamble 9
Wednesday, February 21, 2007
FYI
Quiz (chap 15)
 QP 16 (1-49 odd)
 Garden Project
(look online)
 RLog 10/14
2/23 Friday
3/2 Friday
3/5 Monday
3/12 Monday
Wednesday, February 21, 2007
Acids/Bases
 Acid = produces hydrogen (donor)
 Base = accepts hydrogen (acceptor)
 Acidity and Basicity are measured
using the pH/pOH scales (range 0-14)
 pH = – log [H+]
pOH = – log [OH-]
 pOH + pH = 14
[H+][OH-] = 1 x 10-14
Wednesday, February 21, 2007
Preamble 8
Determine the pH of 100.0 mL of a
1.00 M HCl solution.
Suppose you double the volume of the
solution by adding water. What is the
new pH? You double the volume once
more with water. What is the new pH? If
you continue to add more water, what is
the maximum pH that can be reached?
Explain your answer.
Wednesday, February 21, 2007
Water’s Equilibrium
 Water is ALWAYS in equilibrium
with itself according to the
following equation:
2H2OH3O+ + OH The equilibrium constant for this
reaction is called Kw = 1.0 x 10-14
 Kw = ion product constant
Wednesday, February 21, 2007
Neutralization
 When an acid and base are put
together, they will neutralize each
other.
 If the acid and base contain H and
OH, the reaction will form water.
 H3O+ + OH-  2H2O
Wednesday, February 21, 2007
Preamble 9
 A Lowell student is trying to neutralize 90.0
mL of a 0.400 M solution of the strong base,
Sodium hydroxide so he can put it down the
drain.
 He adds 30.0 mL of a 1.75 M solution of nitric
acid. He then adds 240.0 mL of water.
 Will the resulting solution be neutral? What
will the [H+] and pH be? What is the [OH-] and
pOH? Would the solution turn litmus pink?
Wednesday, February 21, 2007
Agenda
 FYI’s
 Conjugate Acid/Base
 Indicators
Thursday, February 22, 2007
FYI
Quiz (chap 15)
 QP 16 (1-49 odd)
 Garden Project
(look online)
 RLog 10/14
Thursday, February 22, 2007
2/23 Friday
3/2 Friday
3/5 Monday
3/12 Monday
Conjugate Acid/Base Pairs
 To find the conjugate base of an
acid, remove one H
 To find the conjugate acid of a
base, add one H
 Find the conjugate acid/base for
the following:
 H2SO4, C2H3O2-, NH3, HBr, NaOH
Thursday, February 22, 2007
Indicators
 Indicators INDICATE pH via color
 As the pH of the solution changes,
the indicator molecule reacts to the
presence of H+ by rearranging itself
and forming a different color.
 There is no “standard” color for
each pH. Red is not always acid,
blue is not always base
Thursday, February 22, 2007
Agenda
 FYI’s
 Quiz
 Conjugate Acid/Base
 Indicator Lab
Friday, February 23, 2007
FYI
Quiz (chap 15)
 QP 16 (1-49 odd)
 Garden Project
(look online)
 RLog 10/14
Friday, February 23, 2007
TODAY
3/2 Friday
3/5 Monday
3/12 Monday
Conjugate Acid/Base Pairs
 To find the conjugate base of an
acid, remove one H
 To find the conjugate acid of a
base, add one H
 Find the conjugate acid/base for
the following:
 H2SO4, C2H3O2-, NH3, HBr, NaOH
Friday, February 23, 2007
Indicator Lab Questions
1. Draw a color line for each of the
indicators in the lab (one end = acidic,
other = basic)
2. Compare the color lines to the ones in
the book on page 520.
3. Why did the Bromothymol Blue
solution turn yellow? What was the
reaction?
4. What have you learned about
indicators? What were some of the
differences between the indicators?
Friday, February 23, 2007
Agenda
 FYI’s
 Indicator Lab Finish (10
min)
 Garden Project
 Buffers
 Normality
 Preamble 10
Monday, February 26, 2007
FYI
 QP 16 (1-49 odd)
 Garden Project
(look online)
 RLog 10/14
Monday, February 26, 2007
3/2 Friday
3/5 Monday
3/12 Monday
Acid/Base Lab
 Questions: (I saw/ I thought)
1. Draw a color line for each of the indicators
in the lab (one end = acidic, other = basic)
2. Compare the color lines to the ones in the
book on page 520.
3. Why did the Bromothymol Blue solution
turn yellow? What was the reaction?
4. What have you learned about indicators?
What were some of the differences between
the indicators?
Monday, February 26, 2007
Garden Project




Garden center informational brochure
Tri-fold, HANDWRITTEN/DRAWN
4 parts that must be included
“Documents A-D” are there for your
reference. You may also use web sources if
you need more help
 Suggestions:
 Lay out a mock brochure on notebook paper
before making a final version on nice paper
 Use pens/markers instead of pencil for impact
Monday, February 26, 2007
Buffers
 A buffer is a mixture of a weak acid
and its conjugate base
 The conjugate base is typically
balanced with the presence of an alkali
or alkaline earth metal (Groups 1/2)
 If a base is added, it will react with the
weak acid
 If an acid is added, it will react with the
conjugate base
Monday, February 26, 2007
Strong vs. Weak Acids
 Weak acids:




HNO2
HF
HC2H3O2
HCN
Strong acids:
HCl
HBr
HI
HNO3
H2SO4
 You will need to memorize these lists
(suggestion, memorize the strong, all
others are weak)
Monday, February 26, 2007
Normality
 When an acid or a base is dissolved in
water, it produces a certain amount of
H+ or OH Normality is the concentration of H+ or
OH- in the solution
 Often, pH = – log N (instead of –log M)
 Equivalent = amount that provides
1 mol of acid or base
Monday, February 26, 2007
Preamble 10
 Decide which of the following are
strong vs. weak acids and write out their
conjugate bases
 Then, if they are weak acids, write out
the reaction of a buffered solution with
1) HCl and 2) NaOH
 HNO3
HF
HClO4
CH3COOH
HCl
H 2S
Monday, February 26, 2007
Agenda
 FYI’s
 Titration
 Titration Lab
Tuesday, February 27, 2007
FYI
QP 16 (1-49 odd)
 Garden Project
(look online)
 RLog 10/14
Tuesday, February 27, 2007
3/2 Friday
3/5 Monday
3/12 Monday
Preamble 10
 Decide which of the following are
strong vs. weak acids and write out their
conjugate bases
 Then, if they are weak acids, write out
the reaction of a buffered solution with
1) HCl and 2) NaOH
 HNO3
HF
HClO4
CH3COOH
HCl
H 2S
Tuesday, February 27, 2007
Titration
 Titration is a process that determines
the amount/concentration of an
unknown substance in a solution
 The analyte = the unknown (analyzed)
 The titrant = substance reacting with
analyte (titrating the analyte)
 In the Sailin’ the High C’s lab,
Vitamin C = analyte and iodine = titrant
Tuesday, February 27, 2007
Titration
 Titration between a strong acid
and a strong base involves
neutralization
 H+ (from acid) + OH- (from base)  H2O
 In this reaction, the titration is
finished when the pH = 7
 The end = the equivalence point
Tuesday, February 27, 2007
Titration Lab
 You will be given a sample with an
unknown concentration of sulfuric acid
(analyte). Using phenolphthalein as an
indicator and sodium hydroxide as
your titrant, determine the original
concentration of the sulfuric acid
solution.
 You will be given a buret, distilled water,
flasks, and graduated cylinders
 Design a procedure for your experiment
Tuesday, February 27, 2007
Agenda
 FYI’s
 Extra Credit
 Titration Lab
 Preamble 11
Thursday, March 1, 2007
FYI
QP 16 (1-49 odd)
 Acid/Base Lab
 Garden Project
(look online)
TOMORROW
3/5 Monday
3/5 Monday
 RLog 10/14
3/12 Monday
Thursday, March 1, 2007
Extra Credit (bring 1 or 2)








 1 10lb bag of sugar
Gloves (50) M or L
 Straws (100)
Medicine cups (5)
 box of Alka-Seltzer
1 pack Food coloring
 Bottle of Borax
1 box baking soda
 1 large match box
Distilled Water (1 Gallon)
 Sponges
1 25 lb bag of salt (Costco)
1 pack of balloons (12”) (20-25/pack)
1 hour of work after school for Ms. Rotter
 Bring these supplies M-F of next week, they will
apply to this marking period
Thursday, March 1, 2007
Acid/Base Titration Writeup
 You will be doing a formal write-up for
this lab. The sections that should be
included are on the website.
 In your lab notebook should simply be
your data
 The write-up (to be peer reviewed) will
be due on Monday. Make sure there is
a copy for each person in your team.
Thursday, March 1, 2007
Acid/Base Titration





Determine the concentration of the original
sulfuric acid solution
What was the reaction that took place in
your beaker?
What are indications that you are
approaching an endpoint?
What would be the difference if you had
hydrochloric acid instead of sulfuric acid?
What changes would you have seen? Be
specific with numbers.
Design an experiment to determine the
concentration of hydroxide in an unknown
sample.
Thursday, March 1, 2007
Preamble 11
 What ideas do you have about what
happens when ice is added to
water? What happens to both the
water and the ice? Use terms such as
cooling, heating, melting, freezing,
molecular motion/speed and energy.
 Draw a series of pictures to represent
what happens when ice melts into
water. Label as necessary.
Thursday, March 1, 2007
Agenda
 FYI’s
 Extra Credit
 QP 16 Review
Friday, March 2, 2007
FYI
 QP 16 (1-49 odd)
TODAY
 Acid/Base Lab
3/5 Monday
 Garden Project
(look online)
3/5 Monday
 RLog 10/14
3/12 Monday
 QP 10 (1-35 odd)
3/19 Monday
 QP 14 (1-41 odd)
3/26 Monday
 RLog 19
Friday, March 2, 2007
3/29 Thursday
Extra Credit (bring 1 or 2)
Gloves (50) M or L
 Distilled Water (1 Gallon)








Medicine cups (5)
 1 10lb bag of sugar
1 pack Food coloring
 Straws (100)
1 box baking soda
 box of Alka-Seltzer
1 25 lb bag of salt (Costco)
 Bottle of Borax
 1 large match box
Sponges
1 pack of balloons (12”) (20-25/pack)
1 hour of work after school for Ms. Rotter
 Bring these supplies M-F of next week, they
will apply to this marking period
Friday, March 2, 2007
QP 16
(8 min)
 On your whiteboard, put the following
questions from QP 16
 Carbon Cavaliers – # 7 + 9
 Periodic Pros – # 15 + 17
 Avogadro Aces – # 21 + 29
 Kinetic Kids – # 23 + 25
 Equilibrium Experts – # 33
 Reaction Radicals – # 47 + 49
 Solubility Stars – # 43 + 45
 Valance Veterans – # 39 + 41
Friday, March 2, 2007
Acid/Base Titration Writeup
 You will be doing a formal write-up for
this lab. The sections that should be
included are on the website.
 In your lab notebook should simply be
your data
(PLUS FIRST ANALYSIS QUESTION)
 The write-up (to be peer reviewed) will
be due on Monday. Make sure there is
a copy for each person in your team.
Friday, March 2, 2007