Physical and Chemical Properties of Tritium

Tritium Primer

DOE-HDBK-1079-94

PHYSICAL AND CHEMICAL PROPERTIES

PHYSICAL AND CHEMICAL PROPERTIES OF TRITIUM

This section reviews the nuclear properties of tritium and discusses of some of the physical and

chemical properties that are important in understanding tritium handling, containment, and

Nuclear and Radioactive Properties

Being an isotope of hydrogen, tritium has many of the properties of ordinary hydrogen (such as

chemical reactions, permeability, and absorption). Differences may occur because the decaying

tritium atoms can speed up (catalyze) reactions of undecayed tritium, or because atoms that have

undergone decay have changed into helium atoms ( 3He). Additionally, small differences in chemical

reaction rates may result from the relative masses of the isotopes.

Some of the useful properties of tritium are listed in Table 2. Note that the properties listed are those

of T2. The specific activity and power density of HT and DT are approximately one-half those for

T2. The activity density of HT and DT is exactly one-half that of T2.

Table 2 Important nuclear properties of tritium

Half-Life

12.43 yrs

Specific Activity

9,545 Ci/g

Power Density

0.328 W/g

Activity Density

2.589 Ci/cm3

(T2 gas, 1 atm, 0 C)

2.372 Ci/cm3

(T2 gas, 1 atm, 25 C)

Penetration Depths of Beta Particles

The penetration and absorption of beta particles in a material are important factors for detecting

tritium and understanding the mechanisms by which tritium can degrade materials. A beta particle

interacts with matter by colliding with electrons in the surrounding material. In each collision, the

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Tritium