Chemistry? I'm supposed to find the answers on my own, but any help is appreciated
Part 1
Self-Ionization of Water: Read each question carefully and select the best answer. (Each question is worth one point)
1)The self-ionization of water occurs when ____________.
a)water is mixed with salt
b)water molecules are broken apart by adding electricity to the water
c)evaporation occurs
d)water molecules react with each other and transfer H+ ions between them to form OH- and H3O+ molecules
2.Complete the following equation by solving for the question mark: H20 (l) + ? (l) H3O+(aq) + OH- (aq)
a)CH3
b)H2O
c)NaCl
d)N2
3.In the equilibrium reaction of the self-ionization of water, where does the equilibrium lie?
a)slightly to the right (H3O+ and OH- side)
b)far to the left (H20 side)
c)far to the right (H3O+ and OH- side)
d)in the middle
4.When the self-ionization of water occurs, which molecule is called an acid?
a)H2O
b)H3O+
c)OH-
d)N2
5.What color would litmus paper turn in the presence of milk of magnesia?
a)white
b)red
c)blue
d)black
6.How does litmus paper react when exposed to vinegar?
a)It absorbs the extra hydroxide ions and turns blue.
b)It absorbs the extra hydronium ions and turns red.
c)It absorbs the extra protons attached to the hydronium ions and turns red. d)It doesn't react, because vinegar is too weak an acid.
7.Which of the following, when added to water, creates a solution with the highest concentration of hydronium?
a)battery acid
b)vinegar
c)milk
d)milk of magnesia
8.What are the concentrations of H3O+ and OH- in pure water?
a)both 1.0 x 10-7
b)H3O+ 1.0 x 10-7 and OH- 1.0 x 10-9
c)H3O+ 1.0 x 10-4 and OH- 1.0 x 10-10
d)H3O+ 1.0 x 10-10 and OH- 1.0 x 10-4
9.What is the concentration of hydroxide ion in an aqueous solution in which [H3O+] = 1.0 x 10-3 ?
a)1.0 x 10-8
b)1.0 x 10-9
c)1.0 x 10-10
d)1.0 x 10-11
10.If the concentration of H3O+ is greater than 10-7 M, the solution is _________.
a)basic
b)neutral
c)acidic
d)none of the above
11.A basic solution _____________.
a)has a concentration of H3O+ that is greater than 10-7 M
b)is equal to 1 × 10-14 at 25 degrees C
c)has a concentration of OH- that is greater than 10-7 M
d)none of the above
Part 2
The pH Scale: Read each question carefully and select the best answer. (Each question is worth one point)
12.The pH scale __________.
a)has a range from 1-12
b)is used to describe the acidity or basicity of a solution
c)is based on a concentration of 100
d)is not used for liquids
13.Identify the correct equation for pH
a)pH = -log[H3O+]
b)pH = log[H3O+]
c)pH = -log[OH-]
d)pH = log[OH-]
14.A single digit change in pH represents a _____fold change in hydronium ion concentration.
a)one
b)ten
c)hundred
d)thousand
15.If the concentration of hydronium ion is 10-5, the pH is______.
a)7
b)14
c)10
d)5
16.Identify the substance that is the most acidic.
a)milk
b)ammonia
c)lemon juice
d)baking soda
17.Identify the substance that is the most basic.
a)milk
b)ammonia
c)lemon juice
d)baking soda
18.If the pH is 3, what is the hydronium ion concentration?
a)1 × 103 M b)1 × 10-3 M
c)1 × 1030 M d)1 × 10-30 M
19.If the pH is 7, what is the hydronium ion concentration?
a)1 × 104 M b)1 × 10-4 M
c)1 × 10-7 M d)1 × 10-14 M
20.If the pH is 14, what is the hydronium ion concentration?
a)1 × 10-1 M b)1 × 10-4 M
c)1 × 10-7 M d)1 × 10-14 M
21.If the pH is 3, what is the hydroxide concentration?
a)1 × 103 M b)1 × 10-3 M
c)1 × 1011 M d)1 × 10-11 M
22.If the pH is 8, what is the hydroxide concentration?
a)1 × 106 M b)1 × 10-6 M
c)1 × 1014 M d)1 × 10-14 M
Part 4
Answer all of the following questions.
Note to student's:
*To identify a number or other figure as a superscript, place an asterisk (*) before and after the number. For example: 10 cubed = 10*3*
*To identify a number or other figure as a subscript, place an underscore ( _ ) before and after the number. For example: water = H_2_O
(Each question is worth two points)
31. What is the concentration of OH- ions in saturated limewater if [H3O+] = 3.98 × 10-13 M? Is limewater acidic, basic, or neutral?
32. What is the concentration of OH- ions in a potato and water solution if [H3O+] = 1.6 × 10-6 M? Are potatoes and water acidic, basic, or neutral?
33. Analysis of a sample of maple syrup reveals that the concentration of OH- ions is 5.0 × 10-8 M. What is the pH of this syrup? Is it acidic, neutral, or basic?
34. In a sample of bananas and water, it is found that [H3O+] = 2.51 × 10-5 M. What is the corresponding pH value, and are the bananas and water acidic, neutral, or basic?
35. [OH-] = 7.94 × 10-12 M in a sample of vinegar. What is the pH of the vinegar, and is it acidic, neutral, or basic?
