1. Wave-like properties of light include which of the following? I. Interference II. Polarization III. The photoelectric effect

2. Which of the following best explains why hydrogen gas emitted light when electrified?

3. A student designed a procedure to determine the heat of fusion of ice. She constructed a calorimeter using a polystyrene cup and a thermometer. She weighed the cup, filled it with 150 mL of warm water, then weighed the cup and water together. The temperature of the water was measured, and then ice taken from an ice bath temporarily stored in a –20°C freezer was added to the cup. The cup with water and ice was weighed. The student then covered the cup with a polystyrene lid with two small openings. In one opening, she inserted a thermometer and in the other, she inserted a stirring rod to gently stir the contents of the cup until all the ice was melted. The lowest temperature reached by the water in the cup was recorded.Which of the following pieces of information is necessary to calculate the heat of fusion of ice from this data? I. The specific heat of water II. The specific heat of ice III. The thermal conductivity of water IV. The thermal expansion coefficient of ice

4. A student designed a procedure to determine the heat of fusion of ice. She constructed a calorimeter using a polystyrene cup and a thermometer. She weighed the cup, filled it with 150 mL of warm water, then weighed the cup and water together. The temperature of the water was measured, and then ice taken from an ice bath temporarily stored in a –20°C freezer was added to the cup. The cup with water and ice was weighed. The student then covered the cup with a polystyrene lid with two small openings. In one opening, she inserted a thermometer and in the other, she inserted a stirring rod to gently stir the contents of the cup until all the ice was melted. The lowest temperature reached by the water in the cup was recorded. Suppose a significant amount of water from the ice bath adhered to the ice cubes that the student added to the calorimeter. How would this affect the value of the heat of fusion of ice is calculated?

5. A student designed a procedure to determine the heat of fusion of ice. She constructed a calorimeter using a polystyrene cup and a thermometer. She weighed the cup, filled it with 150 mL of warm water, then weighed the cup and water together. The temperature of the water was measured, and then ice taken from an ice bath temporarily stored in a –20°C freezer was added to the cup. The cup with water and ice was weighed. The student then covered the cup with a polystyrene lid with two small openings. In one opening, she inserted a thermometer and in the other, she inserted a stirring rod to gently stir the contents of the cup until all the ice was melted. The lowest temperature reached by the water in the cup was recorded. The purpose of weighing the cup and its contents the third (last) time was to

6. A beam of gaseous hydrogen atoms is emitted from a hot furnace and passed through a magnetic field onto a detector screen. The interaction of the electron of the hydrogen atom and the magnetic field causes the hydrogen atom to be deflected from a straight line path. A tiny, permanent spot develops where an atom strikes the screen. The data produced in this experiment verify which of the following concepts of the atom?

7. Which of the following is true regarding the polarization of the blue light in the experiment?

8. A solid, white crystalline substance is added to water to produce a basic solution. When a strong acid is added to the solution, a gas is liberated. Based on this information, the solid could be:

9. In a laboratory experiment, H2 gas is produced by the following reaction: The H2 gas is collected over water in a gas-collection tube (eudiometer). The atmospheric pressure in the laboratory is 770 torr and the temperature of the lab and the water used in the experiment is 22°C. The vapor pressure of water is 19.8 torr at 22°C. Which of the following gases should not be collected using this technique? I. HCl II. NH3 III. CO2

10. A student weighed 13 grams of blue CoCl2 and placed it on a watch glass at room temperature. Within a few minutes, she observed that the compound turned purple. When she re-weighed the sample, it weighed 17 grams. Several minutes later, it turned red. When she weighed the sample a third time, it weighed 24 grams. The correct formulas of the purple and red hydrates the student observed are:

11. A student added 10 grams of an unknown, nonvolatile solute to 50 grams of water. At 760 torr, the solution boiled at 102°C. If the solute was known to be an ionic compound with a van’t Hoff dissociation factor of 2, the molar mass of the solute is closest to:

12. A colorless solution was aliquoted into 3 test tubes. The following tests were performed: Which of the following ions could be present in the solution at a 0.15-M concentration?

13. In a laboratory experiment, H2 gas is produced by the following reaction: The H2 gas is collected over water in a gas-collection tube (eudiometer). The atmospheric pressure in the laboratory is 770 torr and the temperature of the lab and the water used in the experiment is 22°C. The vapor pressure of water is 19.8 torr at 22°C. The partial pressure of hydrogen gas in the tube is closest to:

14. A beam of gaseous hydrogen atoms is emitted from a hot furnace and passed through a magnetic field onto a detector screen. The interaction of the electron of the hydrogen atom and the magnetic field causes the hydrogen atom to be deflected from a straight line path. A tiny, permanent spot develops where an atom strikes the screen. Which of the following observations was the experiment designed to further study?

15. In the laboratory, which of the following can produce a gas when added to 1 M HCl? I. Zn(s) II. NaHCO3(s) III. 1 M NH3(aq)

16. In another famous experiment, a metal plate was bombarded with photons of different frequencies. At frequencies above 4.4 × 1014 sec−1, electrons were ejected from the metal, hence ionizing it. Which of the following is closest to the ionization energy of the metal in Joules?

17. Particle-like properties of light include which of the following? I. Interference II. Polarization III. The photoelectric effect

18. A photon of red light is produced by an atom. Which of the following expressions accurately calculates its energy?

19. A student performed an experiment at 760 torr. He obtained a sample of an unknown, volatile liquid. He placed it in a 2.00-L Erlenmeyer flask and covered it with a lid containing a tiny pinhole. The student placed the flask in boiling water of 100°C until all the air in the flask escaped through the pinhole and all of the liquid was vaporized. He then immersed the flask in cold water to condense the gas. He dried the flask and determined the mass of the condensed vapor. The mass of the condensed vapor was 3.0 grams. What is the molar mass of the liquid?

20. A student adds aqueous NH3 to a solution of Ni2+ ions and a precipitate forms. When the student adds excess NH3, the precipitate dissolves and produces a deep blue solution. Which of the following best explains why the precipitate dissolved in excess NH3?

21. A cathode ray strikes a detector in a straight line, but when a magnetic or electric field is applied, the path of the ray is deflected. Which of the following particles would not be deflected when passed through an electric field?

22. A steady electric current is passed through molten NaCl for exactly 2 hours producing 230 g of Na metal. The same current is passed through molten FeCl3 for exactly 2 hours. The mass of Fe metal expected to be produced is closest to:

23. A student weighed 13 grams of blue CoCl2 and placed it on a watch glass at room temperature. Within a few minutes, she observed that the compound turned purple. When she re-weighed the sample, it weighed 17 grams. Several minutes later, it turned red. When she weighed the sample a third time, it weighed 24 grams. Ionic compounds that undergo a significant color change when hydrated have which of the following properties?

24. A student determined the percentage of water in a hydrate to be 26 percent by weighing the sample, heating it until dry, and then reweighing it. The accepted value for the percentage of water in the hydrate is 45 percent. Which of the following is the best explanation for the difference between measured and accepted values?

25. A student weighed 13 grams of blue CoCl2 and placed it on a watch glass at room temperature. Within a few minutes, she observed that the compound turned purple. When she re-weighed the sample, it weighed 17 grams. Several minutes later, it turned red. When she weighed the sample a third time, it weighed 24 grams. The CoCl2 compound can be described as all of the following except: