Ch. 12 & 14  chemical bonds & IMF             test     [80 points]       honors Chem

For problems involving calculations, show your work in an organized manner, include any relevant equation (or formula and conversion factor(s)), put the proper units in your calculations / answer, and have the proper number of significant figures in your answer.              

Academic Honesty:   The answers on this test are my own and I am using only the allowed set of notes as described in the syllabus.  I have not discussed the test questions with anyone before or during the test nor have I seen the test questions prior to the exam.  If you violate any of the preceding items or do not sign, your semester grade is a F.

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1.  What is the basis of the covalent bond  ?  [10 points]

2.  In regards to SF4 ,  [15 points]

a.  sketch its Lewis structure(s)

b.  sketch the shape of the molecule

c.  what is the name of the shape of the molecule ?  what is / are the bond angles in the molecule ?

3. In regards to SF4   (see # 2),  [20 points]

a.  rationalize why hybrid orbitals are needed

b.  identify the type of hybrid orbitals needed; justify / rationalize your response.

c.  describe the process of forming the hybrid orbital needed starting from the orbital diagram of the central atom.

d.  use valence bond theory to describe the bonds in this compound

4.  Describe London IMF in a nonpolar compound.  [10 points]

5.  Which compound, CH3 OH versus CH3 CH2 OH, has the larger vapor pressure ?  boiling point ?  Justify / rationalize your response.   [15 points]

6.  What is the basis of adsorption chromatography to separate molecules ?  [10 points]

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Ch. 12 & 14  chemical bonds & IMF             retest  [80 points]                   honors Chem

1.  What is the basis of adsorption chromatography to separate molecules ?  [10 points]

2.  Describe London IMF in a polar compound.  [10 points]

3.  What is the basis of the covalent bond  ?  [10 points]

4.  The boiling point of CHCl3 and CHBr3 is 61 °C and 148 °C, respectively.   [20 points]

a.  Rationalize this observation; identify the IMF in the molecules. 

b.  What is the relative vapor pressure between these chemicals ?  Rationalize your response.

5.  Rationalize why food cooks faster at sea level than on a mountain.  [10 points]

6. In regards to ClF3 ,  [20 points]

a.  draw its Lewis structure

b.  rationalize why hybrid orbitals are needed

c.  identify the type of hybrid orbitals needed; justify / rationalize your response.

d.  describe the process of forming the hybrid orbital needed starting from the orbital diagram of the central atom.

e.  use valence bond theory to describe the bonds in this compound