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```					Acids, Bases, and pH

Notes #7
Forming & Breaking Down Water

 Chemical Reaction Formula of Water
a. H2O H+ + OH-

Water breaks down into 1 Hydrogen ion
(H+) and 1 Hydroxide ion (OH-).
Why is water neutral?
ANS: Ratio of H+ and OH- is equal
*1 positive H+ balances out the 1
negative OH-
The pH Scale
 What does the pH scale measure?
ANS: Measures the amount of H+
in a solution.
-And it ranges from a scale of 0-14
A Closer Look at the pH Scale
a.  Acids: Concentration of H+>OH-
-And ranges from 0-6 in the pH
scale.
- lower the #, stronger the
acid; higher the #, weaker the acid
b. Neutral: Concentration of H+=OH-
-Scale ranges around 7
c. Bases: Concentration of H+<OH-
-Ranges from 8-14
-lower the #, weaker the
base; higher the #, stronger the base
Quick Check
1. If you have a solution with a pH of 7. It is
considered ___________.
a. Basic     b. Acidic       c. Neutral

2). If you have a solution with a pH of 5, then
it is a ____________ acid.
a. strong            b. weak

3) If you have a solution with a pH of 13,then it
is a ____________ base.
a. strong             b. weak.
The pH Scale

QuickTime™ an d a
TIFF (Uncompressed) decompressor
are need ed to see this picture .
What are Acid-Base Indicators?

 ANS: Helps estimate the acid or base
level of a chemical solution.
3 Types of Acid-Base Indicators
1. Blue Litmus Paper:
-In acid it turns from blue to red
-In bases it stays blue
Acid-Base Indicators Cont’d

2. Red Litmus Paper:
-In acid it stays red
-In bases it turns from red to blue
Blue & Red litmus Paper
Testing Unknown Substance
Acid-Base Indicators Cont’d
3. pH paper:
-Accurately measures the pH level
(0-14) of the chemical solution
What are buffers?
ANS: Weak acids or bases that
neutralizes strong acids or bases.

Ex. Pepcid AC or Tums are Ant-acids that
neutralize the over production of
stomach acids.
pH Lab Pre-Lab Write Up
    Write this on your own sheet of
paper
Title (from handout)
I.   Purpose (Summarize into one
sentence)
II. Hypotheses (Copy and complete the
sentences)
III. Materials
III.Materials
1.   Litmus Paper (Blue   8. Soda
& Red)               9. Rubbing alcohol
2.   pH paper & color     10. Antacid
decoder
3.   Apple juice          11. Baking Soda
4.   NaOH                 12. Shampoo
5.   Vinegar              13. Bleach
6.   HCL                  14. Detergent
7. Orange juice           15. Keppel water
16) Milk
IV. Procedure
 Summarize Procedure or bullet main
points

HW: Draw, label, and color the pH scale
Use page 43; Fig 2-10
Quiz 1 Scores
 A = 22-25
 B = 19-21
 C = 17-18
 D = 14.5-16
 F = 0 - 14
#20
 Oxygen-16
 Neutrons= Atomic Mass - # protons
          = 16-8
           = 8 neutrons
 Carbon-14
         Atomic Mass - # protons
        = 14 -6
        = 8 neutrons

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