Chemical Reactivity cont'd - hdbk1113cn10054

DOE-HDBK-1113-98

Module 101 Properties of Uranium

Lesson Plan

Instructor's Notes

Show OT-11

The lower oxidation states, UO2 and U3O8, tend to

be dark brown or black. The higher oxidation

states, UO3 and UO4, are generally orange or

yellow, especially in solution or if water or

crystallization are present (e .g., UO4C2H2O).

Furthermore, the higher oxides usually flake off

more easily and are usually more soluble in water.

Being flaky, they are more easily inhaled. Being

more soluble, they are more easily absorbed into

the body.

Uranyl compounds, such as uranyl nitrate, or

UO2(NO3)2, are chemical forms of uranium that are

often found in solution with water. They are

generally yellow in color and are used in criticality

experiments.

Show OT-10 again

Uranium reacts readily with air and water. For

example, when uranium is machined, small chips

catch fire from the heat of the machining process.

Shavings placed in water react to produce hydrogen

gas. The surfaces quickly oxidize to a hard black

coating that is at first protective; however, under

adverse conditions, it corrodes and flakes.

Uranium also reacts with hydrogen or tritium gas to

form uranium hydride (UH3). Uranium "beds" are

commonly us ed to sto re trit ium.