Chapter 9 Homework
The pH of normal blood is 7.4. The pH of a diabetic's blood was determined to be 6.4. Which comparison of these two blood samples is accurate?
The diabetic's blood is more acidic than normal blood.
Which species is the conjugate acid of HCO3-?
H2CO3
Which pH value indicates the higher concentration of OH-?
pH = 11.4
Which pH value indicates the higher concentration of H3O+?
pH = 5.2
In the acid-base reaction: HCN(aq) + F-(aq) CN-(aq) + HF(aq), where Ka (HCN) = 4.9 × 10^-10 and Ka (HF) = 7.2 × 10^-4, the ________.
reactants are favored
Normal gastric juice has a pH of about 2. Assuming that normal gastric juice is primarily aqueous HCl, what is the concentration of HCl in the stomach?
0.01 M HCl
Which buffer solution has the lowest pH (HF has Ka = 7.2 × 10^-4)?
0.20 M HF and 0.10 M NaF
What is the molarity of an HNO3 solution if 24.1 mL of a 0.250 M Ba(OH)2 solution are needed to titrate a 15.0 mL sample of the acid according to the equation below?Ba(OH)2(aq) + 2 HNO3(aq) 2 H2O(l) + Ba(NO3)2(aq)
0.803 M HNO3
Which solution has the highest pH?
1.0 × 10^-7 M -OH
The pH of a lime is 1.90. What is the [H3O+]?
1.3 × 10^-2 M H3O+
How many milliliters of 0.653 M NaOH are needed to neutralize 25.0 mL of a 1.02 M HBr solution? The neutralization reaction is: NaOH(aq) + HBr(aq) → H2O(l) + NaBr(aq)
39.1 mL NaOH
A solution in which [H3O+] = 7.4 × 10^-5 M has a higher pH than a solution with a [-OH] = 4.8 × 10^-8 M.
False
All salts where the anion is derived from a strong acid form basic solutions.
False
An aqueous solution containing an equal number of moles of Na2HPO4 and H3PO4 is an example of a buffer solution.
False
For a solution labeled 0.15 M CH3COOH, the [H3O+] is 0.15 M.
False
If two solutions differ in their [H3O+] by a factor of 2.0, the difference in their pH will be 2.0.
False
OH- and NH4+ are both examples of Brønsted-Lowry bases.
False
The addition of a base to water decreases the pH of the solution.
False
The pH of a 1.0 × 10^-6 M -OH solution is 6.00.
False
The reactants are favored in the acid-base reaction: HF(aq) + -OH(aq) F-(aq) + H2O(l).
False
Correctly identify the conjugate acid-base pairs in the following equation: HC2H3O2(l) + H2O(l) H3O+(aq) + C2H3O2-(aq)
HC2H3O2/ C2H3O2-and H2O/ H3O+
Which acid has the strongest conjugate base?
Hydrocyanic acid HCN (Ka = 4.9 × 10^-10)
An aqueous solution containing an equal number of moles of NaF and HF is an example of a buffer solution.
True
An aqueous solution of NaHCO3 is basic.
True
Consider two acids, A and B. If acid A is stronger than acid B, then the conjugate base of B is stronger than the conjugate base of A.
True
The acid-base indicator phenolphthalein is colorless in acidic solutions and bright pink in basic solutions.
True
The products are favored in the acid-base reaction: HI(aq) + NH3(aq) NH4+(aq) + I-(aq).
True
The value of Kw applies to any aqueous solution at 25 °C , not just pure water.
True
An Arrhenius base is ________.
a compound that contains hydroxide and dissolves in water to form OH-
A Brønsted-Lowry acid is ________.
a compound that is a proton donor