Name: __________________________ Date: _____________ 1. A sheet of aluminium (Al) foil has a total area of 1.000 ft2 and a mass of 3.636 g. What is the thickness of the foil in millimeters? (density of Al 2.699 g/cm3; 1 ft = 12 in and 1 in = 2.54 cm) A) B) C) D) E) 1.450 x 10-2 mm 929.0 mm 9.290 x 10-2 mm 1.450 x 10-3 mm 1.347 x 10-2 mm 2. The number 1.050 × 109 has how many significant figures? A) B) C) D) E) 4 3 2 6 5 3. Which one of the following is consistent with the postulates of Dalton’s atomic theory? A) In a given chemical compound, the same type of atoms are always present in the same relative numbers. B) The atoms in a given sample of an element are not necessarily identical. C) Matter consists of tiny particles called molecules. D) In chemical reactions, atoms not only rearrange, but also break down into smaller subatomic particles. E) In a given chemical compound, the atoms can be present in different ratios. 4. Which is the correct formula for the binary compound formed of potassium and nitrogen? A) B) C) D) E) K3N KN KN 3 K2N6 K2N4 Page 1 5. A mixture of 13.1 g Zn and 22.0 g I 2 is reacted to completion in a closed, evacuated container. What are the contents of the container after this reaction? Zn + I 2 → ZnI 2 A) B) C) D) E) 27.7 g of ZnI 2 and 7.4 g of Zn 27.7 g of ZnI 2 and 5.7 g of Zn 63.9 g of ZnI 2 and 3.4 g of I 2 63.9 g of ZnI 2 31.2 g of ZnI 2 and 3.9 g of I 2 6. What is the coefficient of O 2 when the following equation is balanced, using the smallest whole number coefficients? C 8 H 18 (l) + O2 (g) → CO(g) + CO 2 (g) + H 2 O(l) A) B) C) D) E) 21 12 15 19 17 7. A 0.1789 g sample of a compound of chromium and chlorine was dissolved in water. All of the chloride ion was then precipitated in the form of AgCl. A mass of 0.4857 g AgCl was obtained. Determine the empirical formula of the compound formed of Cr and Cl. A) B) C) D) E) CrCl 3 CrCl 2 Cr 2 Cl 3 CrCl Cr 3 Cl 2 8. Calculate the de Broglie wavelength (in nm) of a 3000. lb automobile traveling at 55 mile/hr? Given: 1kg = 2.2046 lb , 1km = 0.6214 mile. (Note: lb = pound) A) B) C) D) E) 2.0 x 10-29 nm 25 nm 1361 nm 1.9 x 10-38 nm 1.2 x 10-29 nm Page 2 9. A 1.000 g sample of ethanol, C 2 H 5 OH, was burned in a bomb calorimeter whose heat capacity had been determined to be 2.71 kJ/oC. The temperature of 3.000 kg of water rose from 24.284 oC to 26.225 oC. Determine the ΔH for the reaction in kJ/mol of ethanol? A) B) C) D) E) -1.365 x 103 +1.486 x 103 -3.008 x 104 +3.008 x 104 + 1.971 x 103 10. A certain gas initially at 0.060 L undergoes expansion until its volume is 0.600 L. Calculate the work done (in joules) by the gas if it expands against a constant pressure of 0.400 atm. (1 L·atm= 101.3 J). A) B) C) D) E) –21.9 J –2.67 J –0.219 J –26.7 J –16.3 J 11. Which one of the following processes always results in an increase in the energy of a system? A) B) C) D) E) The system gains heat and has work done on it by the surroundings. The system loses heat and does work on the surroundings. The system gains heat and does work on the surroundings. The system loses heat and has work done on it by the surroundings. The energy of the system is independent of heat only. 12. Photons of light (420 nm) are used to locate the position of a 2.80 g a ball and the uncertainty in the position is equal to one wavelength. What is the minimum uncertainty in the speed of the ball? A) B) C) D) E) 4.50 x 10-26 m/s 3.49 x 10-29 m/s 5.64 x 10-29 m/s 5.64 x 10-26 m/s 6.89 x 10-29 m/s Page 3 13. Which one of the following solutes, dissolved in 1000 g of water, would provide the greatest number of ions? A) B) C) D) E) 0.025 mol of barium chloride 0.020 mol of sodium chloride 0.030 mol of ammonium nitrate 0.035 mol of acetic acid 0.030 mol of calcium sulfate 14. When equal concentrations containing aqueous solutions of hydrofluoric acid (HF) and sodium hydroxide react, which of the following are NOT present in the net ionic equation? I. hydrogen ion II. fluoride ion III. sodium ion IV. hydroxide ion A) B) C) D) E) I and III I and II I, II, and III I and IV II and III 15. Which of the following will give only two resonance structures? I. NO 3 A) B) C) D) E) - II. O 3 III. C 6 H 6 IV CO 3 2- II and III only I and IV only I, II and III only I, II and IV only All of them 16. In which one of the following species is the octet rule violated (not obeyed) by the central atom? A) B) C) D) E) SeCl 4 CH 4 PCl 4 + SO 2 NH 3 Page 4 17. Which one of the following should be the most similar in chemical properties to strontium (Sr)? A) B) C) D) E) 18. Consider the following molecules: CF 2 Cl 2 ; CF 2 H 2 ; CCl 2 H 2 ; CCl 4 What is the correct order for polarity of these molecules (from most to the least polar)? A) B) C) D) E) CF 2 H 2 > CCl 2 H 2 > CF 2 Cl 2 > CCl 4 CF 2 Cl 2 > CF 2 H 2 > CCl 4 > CCl 2 H 2 CF 2 Cl 2 > CF 2 H 2 > CCl 4 > CCl 2 H 2 CF 2 H 2 > CF 2 Cl 2 > CCl 4 > CCl 2 H 2 CF 2 Cl 2 > CF 2 H 2 > CCl 2 H 2 > CCl 4 19. Choose the INCORRECT statement about PCl5 structure. A) B) C) D) E) P has one lone pair of electrons. There are no π bonds. P has sp3d hybridization. Each Cl has 3 lone pairs of electrons. There are 5 σ bonds. 20. According to the molecular orbital (MO) theory, which one of the following molecules will be paramagnetic? A) B) C) D) E) O2 He 2 Li 2 N2 Ne 2 Page 5 21. Calculate the density, in g/L, of chlorine (Cl 2 ) gas at STP. A) B) C) D) E) 3.17 g/L 46.9 g/L 1.58 g/L 2.13 × 10–2 g/L 0.158 g/L 22. How many liters of oxygen gas at 153°C and 0.820 atm can be produced by the decomposition of 22.4 g of solid KClO 3 ? 2KClO 3 (s) → 2KCl (s) + 3O 2 (g) A) B) C) D) E) 11.7 L 0.085 L 4.20 L 7.79 L 3.0 L 23. Oxygen gas at 1.000 atm, placed in a container having a pinhole opening in its side, leaks from the container 2.14 times faster than does an unknown gas placed in this same apparatus at the same pressure. Which one of the following species could be the unknown gas? A) B) C) D) E) SF 6 Cl 2 CO 2 CH 4 F2 24. Palladium (Pd) crystallizes in a face-centered cubic unit cell. Its density is 12.0 g/cm3 at 27C. Calculate the atomic radius of Pd in cm. A) B) C) D) E) 1.38  108 cm 1.95 × 10−8 cm 1.05 × 10−8 cm 1.25 × 10−8 cm 2.05 × 10−8 cm Page 6 25. An example of a covalent network solid is A) B) C) D) E) diamond. potassium. iodine. sodium chloride. carbon dioxide. 26. The atomic planes in a graphite crystal are separated by 335 pm. At what angle would you find the first-order (n = 1) diffraction of 0.154 nm X-rays from a graphite crystal? A) B) C) D) E) 13.3° 66.8° 0.232° 27.4° 2.63° 27. Krypton has a higher melting point than argon because of its A) B) C) D) E) stronger dispersion forces. permanent dipole moment. greater ionization energy. smaller atomic size. higher electron affinity. 28. The molecules in a sample of solid SO 2 are attracted to each other by a combination of A) B) C) D) E) London forces and dipole-dipole interactions London forces only dipole-dipole interactions only covalent bonding only ionic bonding only Page 7 29. What is the simplest formula of a solid containing A, B, and C atoms in a cubic lattice in which the A atoms occupy the corners, the B atoms occupy the body-center position, and the C atoms occupy the faces of the unit cell? A) B) C) D) E) ABC 3 ABC ABC 6 A 4 BC 3 A 8 BC 6 30. The vapor pressure of ethanol is 400. mmHg at 63.5°C. Its molar heat of vaporization is 39.3 kJ/mol. What is vapor pressure of ethanol, in mmHg, at 34.9°C? A) B) C) D) E) 109 mmHg 1510 mmHg 200. mmHg 0.0299 mmHg 4.61 mmHg 31. Calculate the percent by mass of potassium nitrate in a solution made from 45.0 g KNO 3 and 295 mL of water. The density of water is 0.997 g/mL. A) B) C) D) E) 13.3 % 7.57 % 1.51 % 15.2 % 39.9 % 32. Calcium nitrite is used as a corrosion inhibitor in lubricants. What is the molality of a solution prepared by dissolving 18.5 g of calcium nitrite in 83.5 g of distilled water? A) B) C) D) E) 1.68 m 0.0855 m 0.222 m 0.444 m 0.0342 m Page 8 33. What is the freezing point of a solution prepared from 50.0 g ethylene glycol (C 2 H 6 O 2 ) and 85.0 g H 2 O? (K f of water is 1.86°C/m) A) B) C) D) E) -17.6 °C -10.0 °C -1.50°C -15.0°C -2.50°C 34. 0.102 g of a non-ionic compound dissolved in 100. mL of water has an osmotic pressure of 28.1 mmHg at 20°C. Calculate the molar mass of the compound. A) B) C) D) E) 663 g/mol 0.872 g/mol 1.15 g/mol 727 g/mol 1.10 × 102 g/mol 35. Rank the following compounds according to increasing solubility in water. I. CH 3 –CH 2 –CH 2 –CH 3 II. CH 3 –CH 2 –O–CH 2 –CH 3 III. CH 3 –CH 2 –OH IV. CH 3 –OH A) B) C) D) E) I < II < III < IV I < III < IV < II I < II < IV < III III < IV < II < I I < III < II < IV 36. Which one of the following pair will give isoelectronic structures? A) B) C) D) E) V2+ and Cr3+ F and K+ F and F Ca2+ and Mg2+ F- and Cl Page 9 37. What is the hybridization of the central atom in SF 4 ? A) B) C) D) E) sp3d sp2 sp3 sp sp3d2 38. The GeCl 2 molecule has A) B) C) D) E) polar bonds, and is a polar molecule. nonpolar bonds, but is a polar molecule. linear geometry and a nonpolar molecule. polar bonds, but is a nonpolar molecule. nonpolar bonds, and is a nonpolar molecule 39. Aqueous solutions of sodium sulfide and copper(II) chloride are mixed together. Which statement is correct? A) B) C) D) E) CuS will precipitate from solution. Both NaCl and CuS precipitate from solution. No reaction will occur. NaCl will precipitate from solution. A gas is released. 40. Which acid is NOT paired correctly with its formula? A) B) C) D) E) hydrocarbonic acid, H 2 CO 3 hydrocyanic acid, HCN acetic acid, HC 2 H 3 O 2 phosphoric acid, H 3 PO 4 sulfuric acid, H 2 SO 4 Page 10 Answer Key 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A Page 11