Review for Lab Final. 1. Calculate the ph of a solution with [H3O + ] = 2.3 x M. A) B) C) 3.20 D) 11.63

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1 1. Calculate the ph of a solution with [H3O + ] = 2.3 x M. A) B) C) 3.20 D) Calculate the ph of a solution with [H3O + ] = 6.8 x 10-4 M. A) 4.68 B) 4.00 C) 3.17 D) Which of the following concentrations represents an acidic solution? A) [H3O + ] < [OH - ] B) [H3O + ] > [OH - ] C) [H3O + ] = [OH - ] D) All of the above 4. Which of the following statements does NOT correctly describe the Brønsted-Lowry definitions of an acid-base reaction? A) An acid requires a base with which to react. B) An acid-base reaction is a proton transfer reaction. C) An acid-base reaction must occur in an aqueous solution. D) Many acid-base reactions are reversible. 5. Which of the following species is the conjugate acid of H2PO4 -? A) HPO4 2- B) PO4 3- C) H3PO4 D) HPO3-6. Which of the following concentrations represents a basic solution? A) [H3O + ] < [OH - ] B) [H3O + ] > [OH - ] C) [H3O + ] = [OH - ] D) All of the above

2 7. A container has two solutions (A and B) separated by a semipermeable membrane. Initially both compartments have equal volumes. After a period of time, which of the following observations would you expect if side A contains 5% (m/v) glucose and side B contains 5 % (m/v) glucose? A) The volume in side A would rise, and the volume in side B would lower. B) The volume in side B would rise, and the volume in side A would lower. C) The volumes in both side A and side B would rise. D) The volumes in both side A and side B would remain the same. 8. The solubility of KNO3 is 33 g in 100 ml of H2O at 20 o C. What is the maximum number of grams of KNO3 a student could dissolve in 200 ml of water at 20 o C? A) 16.5 g B) 33 g C) 66 g D) 99 g 9. The minority component of the solution is the A) solution. B) solvent. C) solute. D) concentration. 10. Osmosis involves the movement of water across a semipermeable membrane in a direction from concentration to concentration. A) high solute; low solute B) low solute; high solute C) low solvent; high solvent D) low solute; equal solute 11. Which of the following solutes is NOT soluble in water? A) CH3OH B) KCl C) C6H12O6 D) CCl4 Page 2

12. In a container where two solutions are separated by a semipermeable membrane, the more concentrated solution is called A) hypotonic. B) hypertonic. C) isotonic. D) paratonic. 13.

3 12. In a container where two solutions are separated by a semipermeable membrane, the more concentrated solution is called A) hypotonic. B) hypertonic. C) isotonic. D) paratonic. 13. A student performed an experiment in lab to verify Charles' Law. Using the recorded data below, calculate the percent deviation from the theoretical value of Charles' Law. A) 0.939% B) 6.13% C) 1.94% D) 12.1% 14. A volume of 25.0 L at 35K is heated to 350K. What volume does the gas now occupy? A) 2.5 L B) 10 L C) 100 L D) 250 L Page 3

4 15. In lab a student wanted to experimentally verify Charles' Law. To determine the volume in the experimental chamber the student read the markings on the Erlenmeyer flask and recorded 125 ml. Which of the following statements is correct? A) The initial volume recorded would be less than the actual volume of the experimental chamber. B) The initial volume recorded would be greater than the actual volume of the experimental chamber. C) The initial volume would be recorded correctly. D) The initial volume would be recorded incorrectly, but we are unable to tell if the volume is lower or higher than the volume of the experimental chamber. 16. What happens to the density of a gas if the temperature is increased at a constant pressure? A) Density decreases because the volume increases. B) Density decreases because the volume decreases. C) Density remains the same because both volume and temperature are changing. D) Density is not dependent on the temperature of a gas. 17. If the temperature of a gas increases at a constant pressure, what will happen to the volume of the gas? A) The volume of the gas will remain unchanged. B) The volume of the gas will increase. C) The volume of the gas will decrease. D) There is not enough information to determine the change in volume of the gas. 18. If the temperature of a gas is doubled at constant pressure, how does the volume change? A) The volume decreases by half. B) The volume remains the same. C) The volume doubles. D) The change will depend on whether the gas is pure or a mixture of gases. Page 4

5 19. In lab a student is trying to make soap using castor oil and NaOH. Which of the following would be the product soap? A) 3 NaO2C(CH2)10CH3 B) 3 NaC(CH2)10CH3 C) 3 NaO2C(CH2)14CH3 D) 3 NaO2(CH2)10CH3 20. Which of the following can be used to make soap? A) Animal fat B) Coconut oil C) Canola oil D) All of the above 21. An emulsifier is a substance that allows A) polar compounds to mix with each other. B) nonpolar compounds to mix with each other. C) nonpolar and polar compounds to be suspended in the same mixture. D) nonpolar and polar compounds to separate in a mixture. 22. Soap is amphipathic, which means A) it does not react with other compounds. B) it has a monoclinic structure. C) it has both polar and nonpolar regions. D) it creates suds when in solution with water. Page 5

6 23. In lab a student is trying to make soap using tallow and NaOH. Which of the following would be the product soap? A) 3 NaO2C(CH2)14CH3 B) 2 NaO2C(CH2)14CH3 + NaO2C(CH2)16CH3 C) NaO2C(CH2)14CH3 + NaO2C(CH2)16CH3 + NaO2(CH2)7CH=CH(CH2)7CH3 D) 2 NaO2C(CH2)16CH3 + NaO2(CH2)7CH=CH(CH2)7CH3 24. Which of the following statements is NOT correct? A) In a saponification reaction animal fat or plant oil is treated with NaOH or KOH. B) In a saponification reaction it is important to not allow water into the reaction vessel. C) Saponification is the process that can be used to produce soap. D) In a saponification reaction triglycerides readily undergo hydrolysis when treated with lye. 25. In lab two different compounds were run in the same thin layer chromatography conditions. The Rf values for both compounds were calculated to be 0.75 and Which of the following conclusions can be made based on the Rf values calculated? A) The compound with the smaller Rf value is less polar than the substance with the larger Rf value. B) The compound with the smaller Rf value is more polar than the substance with the larger Rf value. C) Both compounds have the same polarity. D) Rf values cannot be used to determine relative polarities between the compounds. 26. Correct application of the samples on the TLC plate is important to the success of the experiment. Which of the following statements is NOT true about the spotting of the sample on the TLC plate? A) If the spot is too large, it may deteriorate the separation of the spots. B) If the spot is too concentrated, it may cause the compounds in the mixture to overlap and spread out. C) If the spot is too large, it will only interact with the mobile phase solvent. D) If the spot is not concentrated enough, no spot will be visible on the plate. Page 6

7 27. What are the two phases used in chromatography to separate the components of a mixture? A) The liquid phase and the solid phase B) The reactive phase and the unreactive phase C) The moving phase and the sitting phase D) The mobile phase and the stationary phase 28. The mobile phase solvent used in a thin layer chromatography experiment is very important for the efficiency of the spot separation. How does the polarity of the solvent affect how well the spots separate on the TLC plate? A) If the solvent is too polar the Rf values will increase for all of the spots and they will remain close together at the origin. B) If the solvent is too polar the Rf values will decrease for all of the spots and they will move right along with the solvent front. C) The polarity of the solvent does not have any impact on the Rf values of the spot. D) Rf values are constant, and changing the solvent will not change the Rf values of the spots. 29. Which of the following statements regarding thin layer chromatography is NOT true? A) It is possible for the Rf value to be greater than 1 if the solvent used is not polar enough. B) Thin layer chromatography can be used to identify the number of components in a mixture. C) It is good practice to spot all of the samples for comparison on the same plate because every TLC plate is slightly different. D) After performing a TLC experiment some spots may appear blank, even when viewing the plate with an ultraviolet light. 30. Which of the following are possible uses of thin layer chromatography? A) To separate and identify the components of a sample B) To determine the number of components in a sample C) To check the purity of a sample D) All of the above Page 7

8 31. Which of the following does NOT describe a monosaccharide? A) A monosaccharide is also known as a simple sugar. B) A monosaccharide generally exists in equilibrium between an open chain form and a ring structure. C) A monosaccharide is a carbohydrate that can be hydrolyzed to a simpler carbohydrate. D) A monosaccharide possesses multiple hydroxyl groups and either an aldehyde or ketone functional group. 32. A positive iodine (I2) test indicates the presence of A) monosaccharides. B) disaccharides. C) polysaccharides. D) reducing sugars. 33. Which of the following describes a polysaccharide? A) A polysaccharide is produced by the hydrolysis reaction of many disaccharide units. B) A polysaccharide is also called a simple sugar. C) A polysaccharide cannot be broken down into simple sugars. D) A polysaccharide is a carbohydrate polymer composed of many monosaccharide subunits. 34. A student is trying to determine the identity of an unknown carbohydrate. As a part of the process, she performs the tests on known samples as well as on distilled water. Why is it important to perform the tests on distilled water? A) Distilled water will show what the test looks like in the absence of any carbohydrates. B) Water is a product in the hydrolysis of carbohydrates. C) The testing solutions contain distilled water. D) The tests need to be performed at a neutral ph. 35. A positive Barfoed's test is used to confirm the presence of A) monosaccharides. B) disaccharides. C) polysaccharides. D) both disaccharides and polysaccharides. Page 8

9 36. Which carbon is the anomeric carbon in the following structure? A) C1 B) C3 C) C5 D) C6 37. How many isomers are there for C3H7Cl? A) 1 B) 2 C) 3 D) A bromine solution is added to an unknown hydrocarbon in a dark hood. As the reaction progresses the solution remains red in color and no change is noted. Upon exposure to a strong light the solution turns colorless. What can be concluded from these observations? A) The unknown is a saturated hydrocarbon. B) The unknown is an unsaturated hydrocarbon. C) The unknown is an aromatic hydrocarbon. D) Not enough information is given to determine the type of hydrocarbon in the unknown. 39. A bromine solution is added to an unknown hydrocarbon in a dark hood. As the reaction progresses the solution remains red in color and no change is noted. Upon exposure to a strong light the solution remains the same. The addition of the catalyst AlCl3 causes the solution to turn colorless. What can be concluded from these observations? A) The unknown is a saturated hydrocarbon. B) The unknown is an unsaturated hydrocarbon. C) The unknown is an aromatic hydrocarbon. D) Not enough information is given to determine the type of hydrocarbon in the unknown. Page 9

10 40. Which of the following type of hydrocarbon would cause the purple color of KMnO4 in solution to turn into a brown color? A) Alkanes B) Alkenes and alkynes C) Aromatics D) Not enough information is given. 41. Name the following alkane: CH3CH2CH2CH2CH3. A) Hexane B) Pentane C) 1-methylbutane D) 1-ethylbutane 42. Which one of the following statements does NOT describe a hydrocarbon? A) A hydrocarbon consists of both carbon and hydrogen atoms. B) A hydrocarbon can have single, double, or triple bonds. C) A hydrocarbon can include additional non-carbon atoms other than hydrogen. D) A hydrocarbon can be saturated or unsaturated. 43. A student trying to prepare aspirin starts with 4.25 g of salicylic acid in the presence of excess acetic anhydride. A student isolates 3.99 g of aspirin in lab. What is his percent yield? C7H6O3 (salicylic acid) + C4H6O3 (acetic anhydride) C9H8O4 (aspirin) + C2H4O2 (acetic acid) A) 93.9% B) 81.7% C) 76.7% D) 72.0% 44. Which of the following methods is recommended for gently agitating a sample in a test tube? A) While wearing gloves carefully place your thumb over the top of the test tube, then agitate by carefully shaking the test tube up and down. B) Use Parafilm secured with a rubber band to cover the opening of the test tube, then agitate by shaking the test tube. C) Hold the test tube between your thumb and split first two fingers, then agitate by flicking the test tube with a finger from the opposite hand. D) Place the test tube in a test tube rack, then agitate by using a stirring rod. Page 10

11 45. The melting point of a solid can be used to determine the purity of a sample. In lab the students synthesized ibuprofen. The literature value for the melting point range of ibuprofen is 75 o -77 o C. Using the following data, determine which sample or samples contain impurities. A) Samples A and B B) Samples B and C C) Samples A and C D) Sample C only 46. Two common methods to prepare esters are used in this lab. Both techniques involve heating of the reaction vessel in a water bath. Why should this be done using a hot plate and not a Bunsen burner? A) The Bunsen burner is too hot. B) Some of the chemicals used are flammable. C) The Bunsen burner causes the water to heat too quickly. D) The Bunsen burner is too difficult to set up when using a water bath. 47. Which of the following compounds does not contain an ester? A) B) C) D) Page 11

12 48. A student calculated a 68.0% yield for her synthesis of aspirin. The mass of the aspirin isolated was 4.35 g. What was the initial amount of salicylic acid used in the reaction? C7H6O3 (salicylic acid) + C4H6O3 (acetic anhydride) C9H8O4 (aspirin) + C2H4O2 (acetic acid) A) 6.40 g B) 4.91 g C) 8.34 g D) 2.96 g 49. A student found that 2.55 grams of calcium carbonate (CaCO3) decomposed to form 1.43 g of calcium oxide (CaO). Carbon dioxide (CO2) was also produced during the reaction. The student's experimental data indicates that the ratio of CaCO3: CaO: CO2 is which of the following? A) 2: 1: 1 B) 3: 1: 2 C) 1: 1: 1 D) 1: 1: Balance the following chemical equation: Fe (s) + H2O (g) H2 (g) + Fe3O4 (s). What is the sum of the coefficients for this balanced chemical equation? If the coefficient is 1, be sure to include it in the total. A) 6 B) 8 C) 10 D) Potassium chlorate decomposes when heated to form potassium chloride and oxygen. In lab a student found that 1.35 g of KClO3 decomposed to form g of KCl. How many grams of oxygen were also formed in this reaction? A) 2.17 g O2 B) 0.53 g O2 C) g O2 D) g O2 Page 12

13 52. During aerobic respiration the following reaction occurs: C6H12O6 + 6 O2 6 CO2 + 6 H2O + heat. Use the balanced chemical equation to calculate the mass of C6H12O6 needed to produce 15.0 g of H2O. A) 25.0 g C6H12O6 B) 2.5 g C6H12O6 C) 0.25 g C6H12O6 D) 900 g C6H12O6 53. In lab a student was performing the decomposition of KClO3. How would the results change if the sample were not heated long enough? A) The mass of KCl would be erroneously high, and the mass of oxygen would be erroneously low. B) The mass of KCl would be erroneously high, and the mass of oxygen would be erroneously high. C) The mass of KCl would be erroneously low, and the mass of oxygen would be erroneously low. D) The length of heating would not change the masses of KCl and oxygen. 54. A student found that 1.45 grams of aluminum (Al) reacted with 1.29 grams of oxygen (O2) to produce 2.74 g of aluminum oxide (Al2O3). The student's experimental data indicates that the ratio of Al: O2: Al2O3 is which of the following? A) 5: 4: 3 B) 1: 1: 2 C) 2: 2: 1 D) 4: 3: When testing for the nutritional minerals in cereal, what is the purpose of ashing the sample? A) To remove the organic molecules from the sample B) To vaporize the minerals so they can be tested C) To test for the presence of the nutritional minerals D) To determine the mass of the minerals in the sample 56. A student obtained an unknown metal from his instructor along with a list of possible metals with their known densities. To determine the identity of the unknown, he decided to calculate the density by measuring the mass and volume of the sample. Which of the following statements is correct? A) The student is using qualitative data to identify the unknown. B) The student is using quantitative data to identify the unknown. C) The student is using qualitative and quantitative data to identify the unknown. D) The student will not have enough data to identify the unknown. Page 13

14 57. A student wants to test a sample for copper ions by adding ammonium hydroxide. The student performs the reaction on a test tube with distilled water, CuCl2 solution, and the unknown sample. The student observes that the unknown sample looks similar to the CuCl2 solution. The student can conclude that A) the unknown sample contains Cu 2+ ions. B) the unknown sample does not contain Cu 2+ ions. C) the unknown sample contains Cl - ions. D) more tests must be done to confirm the presence of Cu 2+ ions. 58. Why should the experiment be performed in the hood during the ashing process? A) Minerals produce toxic fumes when burned. B) The fumes need to be captured to complete the experiment. C) Bunsen burners should be used in the hood. D) The cereal may produce smoke and flames. 59. Based on her observations, a student concludes that iron is not present in her cereal sample. The nutritional label found on the cereal box states that the cereal is iron enriched. Which one of the following is NOT a possible explanation for this contradiction? A) The amount of iron in the sample is too small to be detected. B) The student used tap water instead of distilled water to prepare her sample. C) The student did not completely react the ash with hydrochloric acid. D) The original sample of cereal was not uniform and did not contain any iron. 60. How many moles are in 5.77 g of calcium? A) 231 moles of calcium B) 3.47 x moles of calcium C) moles of calcium D) 6.97 moles of calcium 61. Which of the following molecular formulas have the same empirical formulas? A) Fe2O3 and FeO B) C2H4O2 and C3H6O3 C) C4H8 and C6H6 D) CrCl3 and CrCl2 Page 14

15 62. In a chemical reaction 5.05 g of aluminum was reacted with oxygen to form 9.54 g of aluminum oxide. How many grams of oxygen were required in this reaction? A) 4.49 g oxygen B) 7.58 g oxygen C) g oxygen D) More information is needed. 63. The molecular formula of ammonia is NH3. Which of the following statements regarding the interpretation of the molecular formula for ammonia is INCORRECT? A) Ammonia contains one N atom for every 3 H atoms. B) Ammonia contains one mole of N atoms for every 3 moles of H atoms. C) Ammonia contains one gram of N for every 3 grams of H. D) Ammonia contains grams of N for every grams of H. 64. Which of the following balanced chemical equations represents a reaction that produces the compound formed between chromium (III) and chlorine? A) Cr (s) + Cl (g) CrCl (s) B) 2 Cr (s) + 3 Cl2 (g) 2 CrCl3 (s) C) Cr (s) + 3 Cl (g) CrCl3 (s) D) 3 Cr (s) + Cl2 (g) Cr3Cl2 (s) 65. Which one of the following compounds is an ionic compound? A) NCl3 B) MgCl2 C) CH4 D) H2O Page 15

16 66. Following the typical bonding patterns, how many nonbonding pairs of electrons would need to be added to complete the following structure? A) 5 pairs B) 4 pairs C) 3 pairs D) 1 pair 67. Ionic compounds generally result from A) the sharing of electrons between nonmetal atoms. B) the sharing of electrons between metal and nonmetal atoms. C) the attraction between nonmetal cations and nonmetal anions. D) the attraction between metal cations and nonmetal anions. 68. Consider the molecular formula of CH3CN. How many lone pairs are on the N atom? A) 3 B) 2 C) 1 D) What is the formula for barium hydroxide? A) BaH2 B) Ba(OH)2 C) BaOH D) BaH Page 16

17 Use the following to answer question 70: 70. Tests were performed on a mystery solution to identify the components. A flame test resulted in a yellow flame. The solution did not produce a reaction with the addition of ammonium carbonate, ammonium phosphate, or ammonium sulfate. A halogen test gave no color in the hexane layer. Identify the metal and the halogen ions present in the solution. A) Na, Cl B) Na, Br C) Li, Cl D) Li, Br 71. Group IIA (2) elements are also referred to as A) alkali metals. B) alkaline earth metals. C) halogens. D) noble gases. 72. Elements in the same group have similar chemical properties because they have the same number of A) electrons. B) protons. C) valence electrons. D) neutrons. Page 17

A flame test resulted in a reddish flame. The solution produced a white solid upon addition of ammonium carbonate, ammonium phosphate, and ammonium sulfate.

18 73. An insoluble solid formed in a reaction between two aqueous solutions is called a A) precipitate. B) gel. C) powder. D) solute. Use the following to answer question 74: 74. Tests were performed on a mystery solution to identify the components. A flame test resulted in a reddish flame. The solution produced a white solid upon addition of ammonium carbonate, ammonium phosphate, and ammonium sulfate. A halogen test gave a pale yellow-orange color in the hexane layer. Identify the metal and the halogen ions present in the solution. A) Li, Br B) Li, I C) Ca, Br D) Ca, I Use the following to answer question 75: Page 18

19 75. If you have one gram of each of the following metals, which one would you expect to heat up the fastest? A) Silver B) Lead C) Aluminum D) Iron 76. Energy flows from a warmer object to a cooler one. The flow of energy between the objects is called A) specific heat capacity. B) heat. C) temperature. D) degree Celsius. 77. Inside a typical calorimeter the sample releases energy and heat flows into the water. Which of the following statements is true? A) The heat absorbed by the water is more than the heat released by the sample. B) The heat absorbed by the metal is more than the heat released by the water. C) The heat absorbed by the water is equal to the heat released by the sample. D) The heat absorbed by the water is not related to the heat released by the sample. 78. The amount of heat absorbed by a sample of water is 1250 J. Convert this quantity to joules (1 cal = J). A) 5,230 J B) 3.35 x 10-3 J C) 250 J D) 299 J 79. During an experiment to determine the energy content of food, a student forgets to subtract the mass of the ash remaining. How does this error change the results? A) The food energy content per gram would be calculated higher because the mass is measured high. B) The food energy content would be calculated lower because the mass is measured low. C) The food energy content per gram would be calculated higher because the mass is measured low. D) The food energy content per gram would be calculated lower because the mass is measured high. Page 19

1. The elements on the periodic table are arranged by increasing A) atomic weight. B) atomic number. C) valence electrons. D) mass number.

1. The elements on the periodic table are arranged by increasing A) atomic weight. B) atomic number. C) valence electrons. D) mass number. 2. Periodic law states which of the following? A) Physical and