Chapter 9
1. Describe two properties of an acid and a base.
Acid: sour taste, are electrolytes, turn litmus paper red, neutralize bases, produce H+
ions in water
Base: bitter taste, are electrolytes, turn litmus paper blue, neutralize acids, produce OH
ions in water
2. Where would a 1.00x10-10 molar concentration be on pH scale?
[H3O+] = 1 x 10-10M so pH = 10, basic
3. Label each of the following substances as acidic or basic:
a.
b.
c.
d.
vinegar, acidic
citrus fruit, acidic
aspirin, acidic
black coffee, acidic
4. If the pH is 8, what is the molar concentration?
pH = 8 so [H3O+] = 1 x 10-8M
5. Indicate which of the following is a property of an acid and which is a property of a
base:
a. Sour taste, acid
b. Bitter taste, base
c. Slippery feeling, base
d. Changes color of red litmus to blue, base
e. Changes color of blue litmus to red, acid
6. If the concentration of solution is 1.00x10-12 M, what is the pH of the solution?
[H3O+] = 1 x 10-12M so pH = 12, basic
7. What is the equation for the reaction between Tums, CaCO3(aq), and the HCl(aq) in
stomach acid?
CaCO3(aq) + 2HCl(aq) -------> CaCl2 + H2CO3
8. Write the names of the following compounds:
a. HBr, hydrogen bromide (acid)
b. Ca(OH)2, calcium hydroxide (base)
c. H2SO4, sulfuric acid (acid)
d. KOH, potassium hydroxide (base)
9. How many moles of HCl are dissolved in 200 ml of 0.100 M HCl?
0.100mol/L = M; L = 200mL x 1L/1000mL = 0.200L
M = mol/L so mol = M x L; mol = 0.100mol/L x 0.200L = 0.0200mol
10. What is the molarity of the solutions formed when the following are dissolved to
make 1.0L of solution?
a. 5.0 g of HCl
M = mol/L; grams x FW = mol; 5.0g HCl x 1mol/36g = 0.139mol HCl
M = 0.139mol HCl/1.0L = 0.139M
b. 40.0 g of NaOH
M = mol/L; grams x FW = mol; 40.0g NaOH x 1mol/40g = 1mol NaOH
M = 1mol NaOH/1.0L = 1.0M