1. In the decay series there are six radioisotopes that decay by alpha emission, including Th-232 itself, and four radioisotopes that decay by beta emission. The final product of this series is a stable isotope. What is the symbol for this stable isotope, written in this format?

2. If an object has 25% of the C-14 (t1/2 = 5,730 years) activity as a living organism, the age of the item is

a. 11,460 years b. 17,190 years c. 22,920 years d. 28,650 years

3. Calculate the binding energy per nucleon of an Al-27 nucleus given the following masses: = 26.981541 amu proton = 1.007825 amu neutron = 1.008665 amu

4. ) Calculate the standard cell potential for a galvanic cell in which the following reaction takes place:

Cl2(g) + 2Br-(aq) Æ Br2(l) + 2Cl-(aq)E°cell = _______________ V

Is this reaction spontaneous as written? Yes No (circle one)

5. Balance the following redox reaction in an acidic solution: Sn + NO3- Æ Sn2+ + NO

6.  What is the missing particle? 231 Th Æ _____ + 231 Ac 90 89

a. positron b. beta particle c. alpha particle d. gamma particle