Chem 167 SI:
Final Review Through Exam 2
Supplemental Instruction
Iowa State University / Leader: / Emily and Max
Course: / Chem 167
Instructor: / Burnett
Date: / Dec 14

1.  If 21 g of H2S is mixed with 38 g of O2 and 31 g of SO2 form, what is the percentage yield? 2H2S+3O2→2SO2+2H2O

2.  What is the final molarity of sodium ions if 50.0 mL of 0.25 M Na2SO4 is combined with 50.0 mL of 1.00 M NaCl? Assume the total solution volume is exactly 100.0 mL.

3.  Classify each of the following as a strong acid, weak acid, strong base, or weak base.

  1. NH3
  2. HCl
  3. H2SO4
  4. KOH
  5. CH3COOH
  6. HNO2

4.  Small quantities of hydrogen gas can be prepared by the following reaction: Zns+ H2SO4aq→ZnSO4aq+ H2(g). How many grams of H2 can be prepared from 25.0 mL of 6.00 M H2SO4 and excess zinc?

5.  Which of the following statements about titrations is false?

  1. The reactants are in solution.
  2. The titration should stop when stoichiometric amounts of reactants are combined to obtain meaningful data.
  3. A buret is commonly used to deliver one reactant.
  4. It is not important that the indicator changes color when stoichiometric amounts have been combined.
  5. The indicator is not part of the reaction.

6.  What volume of oxygen at 240C and 0.88 atm is needed to completely react via combustion with 45 g of methane gas?

7.  Which of the following is not a postulate of the kinetic molecular theory of gases?

  1. Gas molecules are in constant random motion
  2. Gas molecules are attracted to each other.
  3. Gas molecules are infinitely small
  4. All gas molecules are the same
  5. Gas molecules have elastic collisions

8.  Which of the following conditions might we expect a gas not to behave like an ideal gas?

  1. High temperature
  2. Low temperature
  3. High pressure
  4. Both (b) and (c)
  5. All three

9.  Find the wavelength of light that would be emitted when a hydrogen atom undergoes the transition from the state n = 4 to the state n = 2. Express your answer in nm. (hint: the wavelength for the transition 4à1 is 97.534 nm, 2à1 121.556 nm, and 3à1102.583 nm)

10.  Which of the following sets of quantum numbers is not possible?

  1. n = 3, l = 2, ml = -1, ms, = +1/2
  2. n = 2, l = 0, ml = 0, ms = +1/2
  3. n = 4, l = 3, ml = 4, ms = -1/2
  4. n = 1, l = 0, ml = 0, ms = +1/2

11.  Which of these electron configurations are for atoms in the ground state? In excited states? Not possible?

  1. 1s22s1
  2. 1s22s22p3
  3. [Ne]3s23p34s1
  4. [Ne]3s23p64s33d2
  5. [Ne]3s23p64f4

12.  Which of the following has the highest second ionization energy Sodium or Magnesium?

13.  Which of the following statements about quantum mechanics theory is incorrect?

  1. Electrons are described as waves
  2. The shrodinger wave equations are fairly simple to solve
  3. The four quantum numbers represent a way to express the information provided by the wave function solution.
  4. The n quantum number describes both potential energy and distance from the nucleus.
  5. The l quantum number describes the region in space occupied by an electron.

14.  Which of the following gives the correct order for atomic radius for Mg, Na, P, Si, and Ar?

  1. Mg>Na>P>Si>Ar
  2. Ar>Si>P>Na>Mg
  3. Si>P>Ar>Na>Mg
  4. Na>Mg>Si>P>Ar
  5. Ar>P>Si>Mg>Na

15.  What is the frequency of yellow light with wavelength of 595 nm?