M8 RadioChem

a) List the most important representatives.

b) What are their typical chemical forms?

2. The radionuclide composition of nuclear explosions and the spent fuel from nuclear power reactors: List the reasons why (or how) the composition of nuclear explosions and the spent fuel from nuclear power reactors differ

3. List 7 factors affecting chemical forms of radionuclides in the environment.

4. Why hydroxide ions (OH–) and carbonate ions (CO32–) are the most important ligands that complex to actinides in the environment?

5. What is the concentration of carbonates in an aqueous solution with a low pH value (pH≤4)?

6. Tetravalent cation Pu4+ may presents only in solutions of a stronger acidity and in non-acidified aqueous solutions immediately hydrolyzes. Why, what happens under those conditions?

7. Water is the dominant transport medium for most elements in the environment. How are the redox potential and pH related to each other and to processes and speciation of elements in environment?

8. Pourbaix diagram is a specific “phase” diagram: briefly describe how it can be used. What do the two dash slope lines stand for?

9. In the Pourbaix diagram for Pu (Fig.2 in Runde’s paper), identify the conditions (pH, eH) where Pu can exist in three different oxidation states, and list the those oxi

10. An increased concentration of carbonates in waters:

a) increases solubility of actinides: how, what it formed?

b) stabilizes the Pu(V) oxidation state: why and under what conditions?

11. There were at least five microbes known that they influence the mobility of actinides or technetium in environment (Livens’s paper). What are the four main environmental processes facilitated by microbes?

12. Citric acid is one of siderophores – what are siderophores and what is their role?

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