Berilium-7 (⁷Be)

Data nuklida

Unsur

Berilium (Be, Z = 4)

Nomor massa (A)

7

Proton (Z)

4

Neutron (N)

3

Massa atom

7.016928714 ± 0.000000076 u

Waktu paruh

53,22 hari (± 0,06 hari)

Mode peluruhan

Penangkapan elektron (ε) ( 100 %)

Inti anak

Litium-7 (⁷Li)

Tahun penemuan

1938

Sumber data

IAEA Atomic Mass Data Center (NUBASE) and IUPAC CIAAW, via PubChem

Kegunaan isotop berilium

• Cosmogenic 10Be and 7Be isotopes are produced in the atmosphere, largely by cosmic-ray spallation of nitrogen and oxygen. Because of its relatively short half-life (7Be, half-life t1/2=53 d, compared to that of 10Be, half-life t1/2=1.39×106 a, where the unit symbol “d” stands for day and “a” stands for year), measurements of cosmogenic 7Be, and especially the isotope-amount ratio n(7Be)/n(10Be), have been used to study rates of atmospheric circulation, mixing, formation of aerosols (fine solids or liquids suspended in a gas; e.g. smoke and mist are aerosols), and particle deposition. Cosmogenic atmospheric beryllium isotopes (7Be and 10Be) are deposited on the Earth’s surface, where they accumulate in soils, sediments, and snow while decaying away. Measurements of cosmogenic beryllium isotopes in such deposits are used to explore rates of soil formation, erosion, sedimentation, and snow accumulation on time scales ranging from months (7Be) to millions of years (10Be),. The minerals in rocks at the Earth’s surface interact with cosmic rays and form substantial quantities of 10Be and 7Be, thus providing a tool to determine the ages of geologic processes. In some situations, it is possible to estimate “exposure ages” for rocks in eroding terrains,,. By comparing measured 10Be concentrations with estimated rates of in situ cosmogenic 10Be production, the rate of rock erosion and formation of canyons and other geologic features can be determined (Fig. IUPAC.4.1). Anthropogenic 10Be was produced by nuclear bomb explosions largely through the reaction of fast neutrons (neutrons produced by nuclear fission having high kinetic energy) with 13C via the 13C (n, alpha) 10Be reaction in atmospheric CO2. Although the quantity of 10Be produced in this way is small, its presence above natural background concentrations in some environmental samples can potentially provide information about bomb-related processes and contamination.

Isotop berilium lainnya

⁵Be, ⁶Be, ⁸Be, ⁹Be, ¹⁰Be, ¹¹Be, ¹²Be, ¹³Be, ¹⁴Be, ¹⁵Be, ¹⁶Be

Pelajari

Kimia inti Simulasi peluruhan ⁷Be Bagan nuklida