c127e3p2f2000

1. A high intensity emission line of Ge occurs at 265.1 nm. What is the energy (in K) of one photon associated with this emission?

   What's your answer? Choose your answer in scientific notation, i.e.,

   ± w.xyz E{± ab}, and then press the Submit button (below).

   + - 1 2 3 4 5 6 7 8 9 . 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 E{ + - 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 }

2. What is the energy in the above question in kJ/mol?

   What's your answer? Choose your answer in scientific notation, i.e.,

   ± w.xy E{± ab}, and then press the Submit button (below).

   + - 1 2 3 4 5 6 7 8 9 . 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 E{ + - 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 }

3. Multiple Choice
   1. Which is the more polar bond?

      C-F N-F O-F F-F Cl-F

   2. Consider the NO₂⁺ species. Which of the following is a true statement?

      The species is linear The species has two different nitrogen-oxygen bond lengths The formal charge of N is 0 The nitrogen is sp-squared hybridized (A),(B),(C) and (D) are true None of the above are true

   3. How many sigma bonds are in the following molecule?

      2 3 5 7 9 12

4. Consider the following molecules whose molecular geometry is given.
   1. O=C=S

      polar non-polar

   2. 

      polar non-polar

   3. 

      polar non-polar

   4. 

      polar non-polar

   5. 

      polar non-polar

   6. 

      polar non-polar

5. Given the Lewis structure of SO₃^2-, the students were asked
   1. for the ideal bond angle between the O-S-O,
   2. the hybridization
   3. the geometry
   and then the same questions were asked for RnF₄.
6. Consider NO₂^-. Draw its Lewis structure and then
   1. Give the number of valence electrons
   2. Give the number of umshared electron pairs (lone pairs) around the central atom
   3. Give the formal charge on N
   4. Give the total number of different resonance structures that can be written
7. 1. Write the Lewis Structure for SeF₄
   2. Write the Geometry for SeF₄
   3. Write the Lewis Strcture for C F₅
   4. Write the Geometry for C F₅
8. Consider an endothermic reaction taking place in a beaker.
   1. Heat flows from the surroundings to the system. True False
   2. The beaker is cold to the touch True False
   3. The pressure of the system decreases True False
   4. The value of q for the system is positive True False
9. Consider the specific heat
   1. Specific heat represents the amount of heat required to raise the temperature of one gram of a substance by 1^oC True False
   2. Specific heat is the amount of heat flowing into the system True False
   3. When 20 J of heat are added to equal masses of different materials at 25^oC the final temperatue for all these materials will be the same. True False
   4. Heat is measured in ^oC True False
10. Consider enthalpy ( H)
    1. It is a state property True False
    2. q_reaction at constant P = H - H_products-H_reactants True False
    3. The magnitude of H is independent of the amount of reactant True False

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Query, are the (above) answers correct?