This document provides information about acids and bases, including: - A table listing the pH of common substances like distilled water, lemon juice, milk, etc. - Characteristics of acids (sour taste, pH less than 7, corrode metal, conduct electricity well) and bases (bitter taste, pH greater than 7, good cleaners, slippery feel) - An explanation of the logarithmic pH scale and how differences in pH values correspond to differences in acidity or alkalinity. - Sample questions to check the reader's understanding of comparing acidity using the pH scale and identifying indicators and examples of strong vs. weak acids.

1. Acids
and
Bases

3. Understanding Acids and
Bases
Distilled Water 7 - ish Saliva 6 -7.4
Tap Water 7.5-8 Battery Acid .5-1
Baking Soda 8.5 - 9 Stomach Acid .5-1
Lemon Juice 2.5-3 Milk 6.5
Normal Rain 5.6-6.5 Ammonia 11-12
Vinegar 2.5-3 Orange Juice 3.5
Drain Cleaner 12 - 14 Cola 2.5-4
(NaOH)

4. Putting it all Together

5. Characteristics of Acids
 Taste sour
 pH less than 7
 Corrode Metal
 Conduct electricity very well (bases will also
conduct electricity but not as well as acids)

6. Characteristics of Bases
 pH greater than 7
 Taste bitter
 Good Cleaners
 Feel slippery

7. Understanding the pH
Scale
Acidic Basic
0 7 14
Neutral
•The pH scale is a logrithmic scale.
•A difference of one pH unit represents a tenfold change
•A difference of 2 pH units, for example from 6 to 4, would mean that
the acidity one hundred times greater.

8. Check Your
Understanding
How many times more acidic is a
tomato than coffee?
10
How many times more acidic is
tomato than saliva?
100
How many times more acidic is lemon
juice than coffee?
1,000

9. What kinds of
Indicators are
there?

10. What makes a solution an acid?
What makes a solution a base?

11. Is There a Pattern
Here?
A = HCl E = HNO3
B = H2SO4 F = H3BO3
C = NaOH G = NH4OH
D = KOH H = CaOH

12. Questions?

13. Acid Base Review

14. What is the pH scale?
 A numerical scale 0-14 that is used to
measure how acidic or alkaline a
substance is.

15. What is phenopthalein?
A base indicator. It turns bright
pink when put into a base.+

16. What is bromythymol blue?
 An universal indicator.
It turns yellow
when placed in an acid. Bright blue in
base. Mostly used to detect carbonic acid.

17. What is Universal Indicator and how
can you use it to test an unknown
solution?
 An acid/base indicator.It turns different
colors depending upon the strength of the
acid and base. You use a color chart to
find the number that corresponds to the
pH scale.

18. How does the pH number of a strong
acid compare to the pH of a weak acid?
 A strong acid will have a pH of 0-1.
 A strong base will have a pH of 13-14

19. What is the difference between an acid
and a base?
 An acid has a H ion.
 A base has a hydroxide ion.

20. What sort of foods are acids?
 lemons, oranges, anything with citric acid.
Also milk is slightly acidic.

21. What sort of liquids are cleaners?
 Bases

22. What do acids taste like?
 sour

23. What liquid is neutral?
 pure water

24. How can you compare strengths of
acids using the pH scale?
 For every number difference on the pH scale, it
is that many power of ten times more acidic.
 Hard to explain…….. For instance….. If you’re
comparing something with a pH of 2 to
something with a pH of 6…. the pH of 2 is ten
thousand times more acidic than the pH of six.
 6-2=4……….. that means it’s 10 to the fourth
power stronger. Ten to the fourth is 10,000

25. What is the pH range of normal rain?
 5.6-6.5

26. What is the pH range of acid rain?
 Below 5.6

27. What acid does carbon dioxide form in
water?
 Carbonic Acid

28. What is meant by the term
"neutralization"?
 Adding base to an acid until it becomes
pH close to 7