21.1. Acid-Base Definitions
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21.1 Acid-Base Definitions
Worksheet
Name _____________________ Class ______________________ Date ________________
Answer each of the questions below to show your achievement of the lesson objectives
Lesson Objective: Describe the properties of acids and bases.
1. All of the following are acids except
1.
2.
3.
4.
citrus fruits
carbonated soda
drain cleaner
vinegar
2. All of the following are properties of acids except
1.
2.
3.
4.
sour taste
aqueous solutions are electrolytes
turn litmus blue
react with some metals to produce H2
3. All of the following are properties of bases except
1.
2.
3.
4.
4.
5.
6.
7.
turn litmus red
bitter taste
do not react with metals
aqueous solutions are electrolytes
True/False: Oranges contain ascorbic acid
True/False: Sodium hydrogen carbonate is an antacid.
True/False: All acids are strong electrolytes.
Fill in the table below
TABLE 21.1:
Property
color with phenolphthalein
color with litmus
taste
reactivity with metals
Acids
Bases
8. Fill in the table below by naming the acid or base contained in the material
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Chapter 21. Acids and Bases Worksheets
TABLE 21.2:
Material
drain cleaner
carbonated soda
vinegar
antacid
cleaners
orange
Acid or Base Present in Material
Lesson Objective: Define an acid and a base according to the Arrhenius theory.
9. An Arrhenius acid is a compound with
1.
2.
3.
4.
reactive hydrogen atoms
ionizable hydrogen atoms
covalently bound hydrogen atoms
hydrogen atoms attached to carbon
10. An Arrhenius base is a compound with
1.
2.
3.
4.
ionizable OH group
covalently bound OH group
reactive OH group
OH group attached to carbon
11. True/False: CH3 CH2 OH is an Arrhenius base.
12. True/False: All Arrhenius bases are completely ionizable.
13. Define the following terms:
1. monoprotic acid
2. polyprotic acid
14. Fill in the blank spaces in the table below:
TABLE 21.3:
Compound
CH3 COOH
Mg(OH)2
Name
hypochlorous acid
phosphoric acid
calcium hydroxide
KOH
sulfuric acid
Lesson Objective: Define an acid and a base according to the Brønsted-Lowry theory. Be able to identify the
conjugate acid-base pairs in a Brønsted-Lowry acid-base reaction.
15. A hydrogen ion is often referred to as a
1.
2.
3.
4.
positron
H atom
proton
portion
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21.1. Acid-Base Definitions
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16. All of the following are true about ammonia except
1.
2.
3.
4.
contains hydroxide group
reacts with acid
turns litmus blue
turns phenolphthalein pink
17. A Brønsted-Lowry acid-base reaction involves
1.
2.
3.
4.
18.
19.
20.
21.
formation of hydroxide ion
transfer of proton
utilization of water
formation of free hydrogen ion
True/False: A hydrogen atom is also called a proton.
True/False: Water can act as a Brønsted-Lowry acid.
True/False: The hydroxide ion is a Brønsted-Lowry acid.
Define the following terms:
1.
2.
3.
4.
5.
Brønsted-Lowry acid
Brønsted-Lowry base
amphoteric
conjugate acid
conjugate base
22. Identify the acid and base and the conjugate acid and base in each of the following reactions:
1. HClO4 (aq) + H2 O(l) H3 O+ (aq) +ClO−
4 (aq)
− (aq) + H SO (aq)
2. HF(aq) + HSO−
(aq)
F
2
3
3
3. HNO2 (aq) + HS− (aq) NO−
2 (aq) + H2 S(aq)
Lesson Objective: Define an acid and a base according to the Lewis theory.
23. A Lewis acid
1.
2.
3.
4.
donates a pair of electrons to form a covalent bond
releases a proton
accepts a proton
accepts a pair of electrons to form a covalent bond
24. A Lewis base
1.
2.
3.
4.
donates a pair of electrons to form a covalent bond
releases a proton
accepts a proton
accepts a pair of electrons to form a covalent bond
25. True/False: Ammonia can serve as a Lewis base.
26. True/False: A Lewis base forms an ionized compound
27. Identify the acid and the base in each Lewis acid-base reaction.
1.
2.
3.
4.
(CH3 )2 O + BF3 → (CH3 )2 O : BF3
H2 O + SO3 → H2 SO4
BeCl2 + 2Cl − → BeCl42−
BH3 + (CH3 )2 S → H3 B : S(CH3 )2
28. A Lewis acid is a substance that accepts a pair of electrons to form a covalent bond. A Lewis base is a
substance that donates a pair of electrons to form a covalent bond. In a Lewis acid-base reaction, a new
covalent bond is formed, but both of the electrons in that bond were originally present on the base.
29. Is the bond formed truly covalent?
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Chapter 21. Acids and Bases Worksheets
30. Why did scientists develop three different classifications for acids and bases?
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21.1. Acid-Base Definitions
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TABLE 21.4:
Property
color with phenolphthalein
color with litmus
taste
reactivity with metals
Acids
colorless
red
sour
good
Bases
pink
blue
bitter
non-reactive
TABLE 21.5:
Material
drain cleaner
carbonated soda
vinegar
antacid
cleaners
orange
Acid or Base Present in Material
sodium hydroxide
phosphoric acid
acetic acid
magnesium hydroxide, sodium hydrogen carbonate
ammonia
citric acid, ascorbic acid
TABLE 21.6:
Compound
CH3 COOH
Mg(OH)2
HClO
H3 PO4
Ca(OH)2
KOH
H2 SO4
Name
acetic acid
magnesium hydroxide
hypochlorous acid
phosphoric acid
calcium hydroxide
potassium hydroxide
sulfuric acid
TABLE 21.7:
Acid
HClO4
HF
HNO2
210
Base
H2 O
HSO3 −
HNO2
Conjugate Acid
H3 O+
H2 SO3
H2 S
Conjugate Base
ClO4 −
F−
NO2 −