Ch. 19 & 14ap nuclear chemistry & kinetics test [65 points] Honors Chemistry

Show your work in an organized manner, includes any relevant equation / formula, proper units in your work / answer, and the proper number of significant figures in your answer.

Academic Honesty: The answers on this test are my own. 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 do not sign or violate any of the preceding items, your semester grade is a F.

Signature: ___________________________


1. Write the (hypothetical ?) nuclear reaction involving [15 points]

a. 35P undergoing positron emission: __________________________

b. the fission of 240Np --> 90Sr + ________

c. the alpha decay of 140Ba: ___________________________


2. What is the age of an object that currently contains 2.5 g 14C, which originally had 7.0 g 14C. The half-life of 14C is 5.73 * 103 years. [10 points]


3. In the combustion of ethane

C2H6 + O2 --> CO2 + H2O

the rate of the consumption of oxygen is 10.0 mM / second. [15 points]

a. what is the rate of consumption of ethane ?

b. what is the rate of appearance of carbon dioxide ?

c. what is the rate of the reaction ?


4. A chemical reaction consumes 45 kJ /mole of heat under constant pressure conditions, where the activation energy for the forward reaction (E a,f) is 35 kJ / mole. [10 points]

a. sketch the reaction energy profile, label E a,b ; E a,f ; ∆H; E reactant ; E product.

b. What is the activation energy of the backward reaction (E a,b) ?

4. What is the rate law (i.e. value of the exponents and rate constant, including its units) in the consumption of ethane (see # 3) based on the following (hypothetical ?) experimental data [15 points]


[C2H6] (M)

[O2] (M)

Rate (mM / s)