Unit 8: Acids/Bases/Salts Addt'l Practice

Transcription

1 Name: Unit 8: Acids/Bases/Salts Addt'l Practice Period: 1. A student tested a 0.1 M aqueous solution and made the following observations: conducts electricity turns blue litmus to red reacts with Zn(s) to produce gas bubbles Which compound could be the solute in this solution? 1) CH3OH 2) LiBr 3) HBr 4) LiOH 2. Which two compounds are electrolytes? 1) C6H12O6 and CH3CH2OH 2) C6H12O6 and HCl 3) NaOH and HCl 4) NaOH and CH3CH2OH 3. As water is added to a 0.10 M NaCl aqueous solution, the conductivity of the resulting solution 1) decreases because the concentration of ions decreases 2) decreases, but the concentration of ions remains the same 3) increases because the concentration of ions decreases 4) increases, but the concentration of ions remains the same 6. According to the Arrhenius theory, a base reacts with an acid to produce 1) ammonia and methane 2) ammonia and a salt 3) water and methane 4) water and a salt 7. When dissolved in water, an Arrhenius base yields 1) hydrogen ions 2) hydronium ions 3) 4) oxide ions 8. How are HNO3(aq) and CH3COOH(aq) similar? 1) They are Arrhenius acids and they turn blue litmus red. 2) They are Arrhenius acids and they turn red litmus blue. 3) They are Arrhenius bases and they turn blue litmus red. 4) They are Arrhenius bases and they turn red litmus blue. 9. According to the Arrhenius theory of acids, citric acid in oranges and acetic acid in vinegar are classified as acids because their aqueous solutions contain 1) hydrogen ions 2) hydrogen atoms 3) 4) hydroxide atoms 4. What can be explained by the Arrhenius theory? 1) the behavior of many acids and bases 2) the effect of stress on a phase equilibrium 3) the operation of an electrochemical cell 4) the spontaneous decay of some nuclei 5. Which compounds are classified as Arrhenius acids? 1) 2) 3) 4) 10. 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.

2 11. Which ph change represents a hundredfold increase in the concentration of H3O +? 1) ph 5 to ph 7 2) ph 13 to ph 14 3) ph 3 to ph l 4) ph 4 to ph Red litmus will turn blue when placed in an aqueous solution of 1) KCl 2) KOH 3) CH3OH 4) CH3COOH 12. Which statement describes the characteristics of an Arrhenius base? 1) It changes blue litmus to red and has a ph less than 7. 2) It changes blue litmus to red and has a ph greater than 7. 3) It changes red litmus to blue and has a ph less than 7. 4) It changes red litmus to blue and has a ph greater than Given the reaction: HX + H2O H3O + (aq) + X (aq), Based on the equation, HX would be classified as 1) a base, because it donates a proton 2) a base, because it accepts a proton 3) an acid, because it donates a proton 4) an acid, because it accepts a proton 13. Given the following solutions: Solution A: ph of 10 Solution B: ph of 7 Solution C: ph of 5 Which list has the solutions placed in order of increasing H + concentration? 1) A, B, C 2) B, A, C 1) bromcresol green 2) bromthymol blue 3) C, A, B 4) C, B, A 14. Which indicator is blue in a solution that has a ph of 5.6? 3) methyl orange 4) thymol blue 18. Given the equation: NH3(g) + H2O( ) «NH4 + (aq) + OH (aq) The two acids acting as proton donors are 1) NH3 and H2O 3) H2O and NH4 2) NH3 and NH4 + 4) H2O and OH 19. In the reaction: H2S + NH3 «NH4 + + HS, The two species that are considered bases are 1) NH3 and NH4 + 3) H2S and NH3 2) NH3 and HS 4) H2S and HS In which 0.01 M solution is phenolphthalein pink? 1) CH3OH(aq) 2) Ca(OH)2(aq) 3) CH3COOH(aq) 4) HNO3(aq) 20. According to an alternative theory, an acid is any species that can 1) donate a proton 2) donate an electron 3) accept a proton 4) accept an electron

3 21. Which equation illustrates the amphiprotic properties of a reactant species? 1) NH2(aq) + H2O( ) NH4 + (aq) + OH (aq) 2) H2O( ) + H2O( ) H3O + (aq) + OH (aq) 3) HCl(aq) + H2O( ) H3O + (aq) + Cl (aq) 4) 2H2(g) + O2(g) 2H2O( ) 22. Which process is used to determine the concentration of an acid? 1) chromatography 2) distillation 1) 1.5 ml 2) 7.5 ml 3) electrolysis 4) titration 23. Which volume of 0.10 M NaOH(aq) exactly neutralizes 15.0 milliliters of 0.20 M HNO3(aq)? 3) 3.0 ml 4) 30. ml 24. How many milliliters of 2.5 M HCl are required to exactly neutralize 15 milliliters of 5.0 M NaOH? 1) 10. 2) 20. 3) 30. 4) Which solution will be exactly neutralized by 1.0 liter of 1.0M NaOH? 1) 1.0 liter of 0.50M HCl 2) 1.0 liter of 2.0M HCl 3) 0.50 liter of 0.50M HCl 4) 0.50 liter of 2.0M HCl 27. When HCl(aq) is exactly neutralized by NaOH(aq), the hydrogen ion concentration in the resulting mixture is 1) always less than the concentration of the 2) always greater than the concentration of the 3) always equal to the concentration of the 4) sometimes greater and sometimes less than the concentration of the 28. 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 2) BaSO2 3) BaSO3 4) BaSO4 29. Which reactants form the salt CaSO4(s) in a neutralization reaction? 1) H2S(g) and Ca(ClO4)2(s) 2) H2SO3(aq) and Ca(NO3)2(aq) 3) H2SO4(aq) and Ca(OH)2(aq) 4) SO2(g) and CaO(s) 30. Which compound could serve as a reactant in a neutralization reaction? 1) NaCl 2) KOH 3) CH3OH 4) CH3CHO 26. A 16-milliliter sample of 0.50 M KOH will completely neutralize 32 milliliters of 1) 1.0 M HNO3 2) 0.75 M HNO3 3) 0.50 M HNO3 4) 0.25 M HNO3 31. 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 Base your answers to questions 32 and 33 on the passage below. Acid rain is a problem in industrialized countries around the world. Oxides of sulfur and nitrogen are formed when various fuels are burned. These oxides dissolve in atmospheric water droplets that fall to earth as acid rain or acid snow. While normal rain has a ph between 5.0 and 6.0 due to the presence of dissolved carbon dioxide, acid rain often has a ph of 4.0 or lower. This level of acidity can damage trees and plants, leach minerals from the soil, and cause the death of aquatic animals and plants. If the ph of the soil is too low, then quicklime, CaO, can be added to the soil to increase the ph. Quicklime produces calcium hydroxide when it dissolves in water. 32. Samples of acid rain are brought to a laboratory for analysis. Several titrations are performed and it is determined that a 20.0-milliliter sample of acid rain is neutralized with 6.50 milliliters of M NaOH. What is the molarity of the H + ions in the acid rain? 34. A student recorded the following buret readings during a titration of a base with an acid: a Calculate the molarity of the KOH. Show all work. b Record your answer to the correct number of significant figures. 33. A sample of wet soil has a ph of 4.0. After the addition of quicklime, the H + ion concentration of the soil is of the original H + ion concentration of the soil. What is the new ph of the soil sample?

5 35. Base your answer to the following question on the information and data table below. A titration setup was used to determine the unknown molar concentration of a solution of NaOH. A 1.2 M HCl solution was used as the titration standard. The following data were collected. Explain why it is better to use the average data from multiple trials rather than the data from a single trial to calculate the results of the titration.