ACIDS AND BASES

Chapter 4 Section 4.4 Acid Base Reactions (150 – 157)Chapter 18 Section 18.1, 18.2, 18.3

Problems:Chapter 18: 5, 7, 21, 23, 24, 43, 44Chapter 4: 43, 44, 49, 53, 54

Concepts:Definitions of acids/bases

Arrhenius definitionBronsted-Lowry definition

Strong and weak acids/basesConjugate acid/base pairsAutoionization of waterpH, pOHmolarityNeutralization reactions

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1. Listed below are some of the properties of acids and bases. Fill in the blanks with the appropriate word, acids or bases:

a) __________ produce hydrogen ions (H+) in solution e) __________ have a sour taste

b) __________ have a bitter taste f) __________ have a slippery, soapy feel

c) __________ produce hydroxide ions (OH-) ions g) __________ react with acids to form salts

d) __________ react with bases to form salts h) ___________ react with many metals

2. List 3 strong acids and explain why these acids are considered strong acids.

3. List 3 weak acids and explain why these acids are considered weak acids.

4. List 2 strong bases and explain why these bases are considered strong bases.

5. List 1 weak base and explain why it is considered a weak base.

NAMING REVIEW

Name of ion Formula for ion Formula for acid Name of acidSulfate

Sulfurous acid

S2-

Nitrite

H3PO4

Acetic acid

Cl1-

PO33-

Hydrobromic acid

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For the following acids or bases, complete the charts below.

Acid Conjugate base Base Conjugate acid

H2SO4 H2O

NH41+ HSO4

1-

H2O HPO42-

HI NH3

H2CO3 O2-

H3PO4 NO31-

For the following Bronsted-Lowry acids or bases, complete the reaction. Label the acid and base and the conjugate acid and base.

HI + H2O

NH3 + H2O

HNO3 + H2O

6. Write a balanced equation for the dissociation (ionization) of the following acids in water (For those acids that are strong use a single arrow, , and for those that are weak you need to use a double arrow, )

a) HClO4 H1+(aq) + ClO41- (aq)

b) H2SO4

c) HC2H3O2

d) HCl

e) HNO3

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7. Write an equation for the dissociation (ionization) of the following bases in water. (For those acids that are strong use a single arrow, , and for those that are weak you need to use a double arrow, )

a) NaOH

b) Ca(OH)2

c) Ba(OH)2

d) KOH

e) LiOH

f) NH3 + HOH

Calculate the appropriate values for pH, pOH, hydronium ion and hydroxide ions in the following tables.

pH [H3O+] pOH [OH-] Acidic or basic

2.0

1 x 10-3

1 x 10-4

8.0

9.0

10.0

1 x 10-5

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[H+] (Mol/L) [OH-] (Mol/L) pH pOH Acid, Base, or neutral

1.34 10-6

2.54 10-10

2.6

5.9

2.76 10-1

9.25 x 10-2

12.5

2.89

3.45 x 10-7

2.75 x 10-6

5.55

4.67 x 10-8

2.55 x 10 -11

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7

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When an acid and base neutralize each other, what two substances are formed?

9. Write and balance the neutralization reactions for the followinga. HBr + KOH

b. HCl + LiOH

c. HF + Ba(OH)2

d. H2SO4 + LiOH

e. H3PO4 + NaOH

f. H2SO4 + Al(OH)3

g. H3PO4 + Mg(OH)2

h. Phosphoric acid + silver hydroxide

i. Nitric acid + Iron (III) hydroxide

10. When titrating an acid with a base, how do you know that you have reached the end of the titration?

11. What indicator is clear in an acid and pink in a base?

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12. A student pours exactly 26.9 mL of HCl acid of unknown concentration into a beaker. The student then adds 2 drops of the indicator spelled correctly in question #4 above and titrates the acid to neutrality using 43.7 mL of 0.13 M NaOH base.

a. Write and balance the neutralization reaction of the acid and base.

b. What is the concentration (molarity) of the acid?

13. A student makes an acid by dissolving 34 grams of KHSO4 in enough water to make 150 mL of solution. The student then uses 32.6 mL of the KHSO4 acid to titrate 12.1 mL of a KOH base of unknown molarity.

a. Calculate the concentration of the acid

b. Calculate the molarity of the KOH base solution

14. In a laboratory, you make a base by adding 75.0 grams of NaOH to enough water to make 380 mL of solution. Then you titrate 15.0 mL of your base using a nitric acid (H2SO4) that is 1.20 M.

a. Calculate the molarity of the base

b. How many mL of the 1.2 M sulfuric acid will be required to titrate the 15.0 mL of base?

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15. A student makes a standard acid by dissolving 4.00 grams of oxalic acid dihydrate (H2C2O4 2H2O) in enough water to make 250.0 mL of solution.

a. What is the molarity of the standardized acid?

b. The student then uses 45.0 mL of the standard acid to neutralize 20.0 mL of NaOH. What is the molarity of the base?

c. The student then uses the base from part (b) to titrate 20.0 mL of an 0.32 M HCl solution. How many mL of the base are needed to completely neutralize the HCl?

16. An 8.0 L tank containing sulfuric acid is neutralized when 5.0 g of Na metal is added. (an extremely foolish thing to do). Calculate the molarity of the sulfuric acid and the pH of the original solution.

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Acid/Base Anhydrides:Complete the following reactions:

Na2O + H2O

SO3 + H2O

Mg(OH)2

€

heat ⏐ → ⏐CaO + H2O

H2SO3

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heat ⏐ → ⏐Complete the following statements:

The salt formed form the reaction of nitric acid and potassium hydroxide is ______________________________.

The conjugate base of H2PO41- is _________________________________________.

Stomach acid is ______________________________________________.

Something with a sour taste is ______________________________________.

Ammonia is an example of ________________________________________.

A pH less than 7 indicates _________________________________________.

Phenolphthalein turns ___________________________________________________ in base.

Red litmus turns blue in ________________________________________________.

A substance that reacts with metals to form hydrogen gas __________________________________________.

A substance that tastes bitter is probably _____________________________________________.

An Arrhenius acid is ___________________________________________.

Will a basic solution conduct electricity? _____________________________.

What is the name of a substance that can donate two protons? ______________________________________.

What is the name of a substance that can both donate and accept a proton? ____________________________

Give two examples of this type of substance. __________________________________________________

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