Quiz Corrections: Check each response. Change the response by highlighting the correct answer (in a color that’s not yellow). Correct each wrong answer choice; write one sentence why the correct answer is right and why the wrong answer is incorrect (2 sentences for each question).

24 questions = 72 points total = 1 point for the correct answer, 1 point for explaining the right answer, 1 point for explaining the wrong answer

1. An Arrhenius acid has
(1) only hydroxide ions in solution (2) hydrogen ions as the only negative ions in solution
(3) hydrogen ions as the only positive ions in solution (4) only hydrogen ions in solution

There are many key points to identifying Arrhenius acids. Choice 4 is incorrect because it does not talk
about any charges (positive or negative). Choice 3 is correct because it states that the hydrogen ions
are positive and ONLY positive ions are in the solution.

2. Which 0.1 M solution contains an electrolyte?
(1) C6H12O6(aq) (3) CH3OH(aq)
(2) CH3COOH(aq) (4) CH3OCH3(aq)

3. Which equation represents a neutralization reaction?
(1) Na2CO3 + CaCl2 → 2 NaCl + CaCO3
(2) Ni(NO3)2 + H2S → NiS + 2 HNO3
(3) NaCl + AgNO3 → AgCl + NaNO3
(4) H2SO4 + Mg(OH)2 → MgSO4 + 2 H2O

4. Use this prompt for questions 4-6: A truck carrying concentrated nitric acid overturns and spills its contents. The acid drains into a nearby pond. The pH of the pond water was 8.0 before the spill. After the spill, the pond water is 1,000 times more acidic.
Name an ion in the pond water that has increased in concentration due to this spill. hydroxide

5. What is the new pH of the pond water after the spill? 6.0

6. What color would bromthymol blue be at this new pH? Green

7. What is the only positive ion in an aqueous solution of carbonic acid? H 2+

8. Which of these pH numbers indicates the highest level of acidity?
(1) 5 (3) 10
(2) 8 (4) 12

9. According to the Arrhenius theory, when a base dissolves in water it produces
(1) CO3 2– as the only negative ion in solution
(2) OH– as the only negative ion in solution
(3) NH4+ as the only positive ion in solution
(4) H+ as the only positive ion in solution

10. Which compound is an electrolyte?
(1) C6H12O6 (3) CaCl2
(2) CH3OH (4) CCl4

11. A student neutralized 16.4 milliliters of HCl by adding 12.7 milliliters of 0.620 M KOH. What was the molarity of the HCl acid?
(1) 0.168 M (3) 0.620 M
(2) 0.480 M (4) 0.801 M

12. Which process uses a volume of solution of known concentration to determine the concentration of another solution? (1) distillation (3) transmutation (2) substitution (4) titration

13. Which pH change represents a hundredfold increase in the concentration of H3O+?
(1) pH 5 to pH 7 (3) pH 3 to pH 1
(2) pH 13 to pH 14 (4) pH 4 to pH 3

14. Which compound is an Arrhenius base? (1) CH3OH (3) LiOH (2) CO2 (4) NO2

15. Which statement correctly describes a solution with a pH of 9?
(1) It has a higher concentration of H3O+ than OH– and causes litmus to turn blue.
(2) It has a higher concentration of OH– than H3O+ and causes litmus to turn blue.
(3) It has a higher concentration of H3O+ than OH– and causes methyl orange to turn yellow.
(4) It has a higher concentration of OH– than H3O+ and causes methyl orange to turn red.

16. According to Reference Table M, what is the color of the indicator methyl orange in a solution that has a pH of 2? (1) blue (3) orange (2) yellow (4) red

17. Given the reaction: NH3 + HCl → NH4Cl In this reaction, ammonia molecules (NH3) act as a base because they
(1) accept hydrogen ions (H+) (2) accept hydroxide ions (OH–)
(3) donate hydrogen ions (H+) (4) donate hydroxide ions (OH–)

18. Sulfuric acid, H2SO4(aq), can be used to neutralize barium hydroxide, Ba(OH)2(aq). What is the formula for the salt produced by this neutralization? (1) BaS (3) BaSO3 (2) BaSO2 (4) BaSO4

19. In which solution will thymol blue indicator appear blue?
(1) 0.1 M CH3COOH (3) 0.1 M HCl (2) 0.1 M KOH (4) 0.1 M H2SO4

20. Which indicator is yellow in a solution with a pH of 9.8?
(1) methyl orange (3) bromcresol green (2) bromthymol blue (4) thymol blue

21. How many milliliters of 0.100 M NaOH(aq) would be needed to completely neutralize 50.0 milliliters of 0.300 M HCl(aq)? (1) 16.7 mL (3) 150. mL (2) 50.0 mL (4) 300. mL

22. Identify two indicators from Reference Table M that are yellow in solutions with a pH of 5.5. phenolphtlaein and bromcresol green

23. Use the following prompt for questions 23 and 24: Sulfur dioxide, SO2, is one gas produced when fossil fuels are burned. When this gas reacts with water in the atmosphere, an acid is produced forming acid rain. The pH of the water in a lake changes when acid rain collects in the lake. Two samples of the same rainwater are tested using two indicators. Methyl orange is yellow in one sample of this rainwater. Litmus is red in the other sample of this rainwater.

Identify a possible pH value for the rainwater that was tested. 4.0

24. Write the formula for one substance that can neutralize the lake water affected by acid rain. NaCl