Name:  ______________________________                                                      period:  _______

Ch. 21 & 14  Nuclear chem. & kinetics  test             [70 points]                   Chemistry

For problems involving calculations, show the relevant equation (or formula and conversion factor(s)), show your work in an organized manner, 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.

                                                                        Signature:  ___________________

1.  fill-in the blank for the following (hypothetical ?) nuclear reaction.  [15 points]

a.  210Pb  à  4He +    ______

 

b.  32P  ->  +   _____

 

c.  29Al  à  +   ____

 

d.  4He  +  15N  à   ______

 

e.  240U  à  3 neutrons  +  140Ba  +  _____ 

 

2.  14C has a half-life of 5.73 * 103 years.  A sample currently has 15 mg 14C, but originally had 85 mg 14C.  What is the age of the sample ?  [10 points]

 


3.  If the rate of combustion of ethane (CH3CH3) is  - 5.0 mM / second, then what is the  [20 points]

a.    rate of appearance of carbon dioxide ?

 

 

 

 

 

 

b.  rate of appearance of water ?

 

 

 

 

 

c.  rate of disappearance of oxygen ?

 

 

 

 

 

d.  rate of the reaction ?

 

 


4.  Based on the following (hypothetical ?) experimental data,


Expt

[N2]  (M)

[H2]  (M)

Rate  (mM / sec)

1

1.0

1.0

1.0

2

1.0

2.0

2.0

3

2.0

1.0

4.0

for the reaction:  N2  +  H2  à  NH3, what is the rate law of the reaction (include the value of the exponents & rate constant, including its units)    [15 points]

 

5.  The ΔHreaction = - 35 kJ / mole;  Ea, backward = 15 kJ / mole.   [10 points]

a.  sketch and label the reaction energy profile

b.  calculate Ea, forward