Exam III Review

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Exam III Review

• Chemistry 1211
• Dr. Clower

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• 1. A balloon contains 3.2 x 10-2 m3 of nitrogen
  gas at a pressure of 712 mm Hg. What is the
  volume of the balloon in liters and the pressure
  in atmospheres?
• 3.2 x 10-5 L and 0.712 atm
• 3.2 x 10-5 L and 0.937 atm
• 3.2 x 10-1 L and 1.00 atm
• 3.2 x 101 L and 0.712 atm
• 3.2 x 101 L and 0.937 atm

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• 2. All of the following relationships are false
  for gases EXCEPT
• Volume is inversely proportional to the moles of
  gas
• Volume is directly proportional to pressure in mm
  Hg
• Volume is directly proportional to pressure in
  atmospheres
• Volume is directly proportional to temperature in
  Kelvin
• Volume is directly proportional to the gas
  constant R

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• 3. Avogadro's law states that
• 1 liter of any gas contains 6.02 x 1023 gas
  molecules
• The volume of a gas is directly proportional to
  its temperature
• The gas constant equals 0.0821 L ? atm/mol ? K
  for all ideal gases
• The volume of a gas must always be a constant
• Equal volumes of all gases at the same pressure
  and temperature contain an equal number of moles

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• 4. The lid is tightly sealed on an empty 2.0 L
  soda bottle at 27.0ºC and 748 mm Hg. If the
  bottle is heated to 100.0ºC, what is the pressure
  inside the bottle?
• 63 mm Hg
• 210 mm Hg
• 620 mm Hg
• 930 mm Hg
• 1300 mm Hg

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• 5. If 6.00 g of nitrogen gas (N2) is introduced
  into an evacuated 2.00 L flask at 28ºC, what is
  the pressure inside the flask?
• 0.246 atm
• 1.83 atm
• 2.65 atm
• 15.8 atm
• 74.1 atm

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• 6. What volume does 22.4 moles of hydrogen gas
  occupy at 0ºC and 1.00 atm?
• 0.0821 L
• 1.00 L
• 22.4 L
• 184 L
• 502 L

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• 7. A 10.0 L flask contains 14.1 grams of an
  unknown gas. If the pressure in the flask is 2.3
  atm at 65ºC, which of the following is a possible
  identity of the gas?
• NH3
• CO
• O2
• CO2
• CS2

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• 8. What is the density of argon gas at 25ºC and
  1.00 atm?
• 0.0110 g/L
• 1.63 g/L
• 19.5 g/L
• 977 g/L
• 1.24 x 103 g/L

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• 9. If 5.00 L of propane is burned in 21.0 L of
  oxygen, what volume of carbon dioxide is
  produced? Assume that the temperature of the
  reactants and products is 25ºC and the pressure
  of the system remains constant at 1.0 atm.
• C3H8(g) 5O2(g) ? 3CO2(g) 4H2O(g)
• 12.6 L
• 15.0 L
• 21.0 L
• 25.6 L
• 26.0 L

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• 10. The composition (in mole percent) of the
  atmosphere is 78.1 N2, 21.0 O2, and 0.9 Ar.
  What is the partial pressure of each gas when the
  barometric pressure is 754.1 mm Hg?
• N2 21.1 atm, O2 6.5 atm, Ar 0.3 atm
• N2 78.1 mm Hg, O2 21.0 mm Hg, Ar 0.9 mm Hg
• N2 244 mm Hg, O2 244 mm Hg, Ar 244 mm Hg
• N2 405 mm Hg, O2 234 mm Hg, Ar 293 mm Hg
• N2 589 mm Hg, O2 158 mm Hg, Ar 7 mm Hg

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• 11. All of the following are properties of gases
  according to the kinetic theory EXCEPT
• Gases consist of mostly empty space
• Attractive forces cause gas molecules to collide
• Gas pressure is caused by collisions of molecules
  with the container walls
• Collisions between gas molecules are elastic
• Gas molecules are in constant motion

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• 12. One way in which real gases differ from ideal
  gases is that the molecules of a real gas
• Have no kinetic energy
• Move in curved paths
• Have no mass
• Occupy no volume
• Are attracted to each other

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• 13. A pair of electrons that is shared between
  two atoms is
• a covalent bond.
• a lone pair.
• a double bond.
• an ionic bond.
• both a covalent bond and a double bond.

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• 14. How many electrons are available for bonding
  in phosphate ion, PO43-?
• 30
• 31
• 32
• 36
• 50

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• 15. Which of the following is a correct Lewis
  structure for C2H6O?
• Answers a and c are correct.
• Answers a, b, and c are correct

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• 16. Which Lewis structure is possible for N2O?

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• 17. Which of the following elements is most
  likely to form a molecule or ion that exceeds the
  octet rule?
• Na
• S
• B
• F
• C

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• 18. What is the correct Lewis structure of XeF4?

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• 19. Which of the following species has a Lewis
  structure with a molecular geometry similar to
  NH3?
• CO32-
• BH3
• H3O
• ICl3
• SO3

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• 20. What is the formal charge on each atom in
  CN-?
• C 0, N 0
• C 1, N -1
• C -1, N 0
• C 2, N -3
• C 4, N -5

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• 21. Use VSEPR theory to predict the molecular
  geometry of IF5.
• octahedral
• square planar
• tetrahedral
• see-saw
• square pyramidal

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• 22. What are the bond angles in CO32-?
• 90º
• 109.5º
• 120º
• 90º and 120º
• 180º

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• 23. Which of the following molecules contain
  polar covalent bonds CO, N2, NH3, NH4, and HCl?
  
• CO and HCl
• CO and NH3
• CO, NH3, and N2
• CO, NH3, NH4 and HCl
• All of the species contain polar covalent bonds.

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• 24. What is the hybridization of the central atom
  in XeF4?
• sp
• sp2
• sp3
• sp3d
• sp3d2

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• 25. What hybridization change does the carbon
  atom undergo in the combustion of methane?
• CH4 (g) 2 O2 (g) ? CO2 (g) 2 H2O (g)
• sp ? sp2
• sp2 ? sp3
• sp3 ? sp
• sp2 ? sp
• none

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• 26. How many sigma and pi bonds are present in
  the following molecule?
• 8 sigma bonds and 1 pi bond
• 8 sigma bonds and 2 pi bonds
• 10 sigma bonds and 2 pi bonds
• 11 sigma bonds and 2 pi bonds
• 11 sigma bonds and 1 pi bond