Boron-20

Properties and data of the isotope ²⁰B.

Content

General data

Name of the isotope:Boron-20; B-20Symbol:²⁰B or 205BMass number A:20 (= number of nucleons)Atomic number Z:5 (= number of protons)Neutrons N:15Isotopic mass:20.07348(86) u (atomic weight of Boron-20)Nuclide mass:20.0707371 u (calculated nuclear mass without electrons)Mass excess:68.44618 MeVMass defect:0.095618900000002 u (per nucleus)Nuclear binding energy:89.06843164 MeV (per nucleus)
4.45342158 MeV (average binding energy per nucleon)Half-life:< 260 nsDecay constant λ:2665950.6944613 s^-1Specific activity α:8.027365303846 × 10⁺²⁸ Bq g^-1
2.169558190228 × 10⁺¹⁸ Ci g^-1Spin and parity:
(nuclear angular momentum)(1-. 2-)Year of discovery:2018

Radioactive Decay

Half-life T_½ = < 260 ns respectively 2.6 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
n	¹⁹B

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 15) and isobaric (same nucleon number A = 20) with Boron-20. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 15	Isobar A = 20
5	²⁰B	²⁰B
6	²¹C	²⁰C
7	²²N	²⁰N
8	²³O	²⁰O
9	²⁴F	²⁰F
10	²⁵Ne	²⁰Ne
11	²⁶Na	²⁰Na
12	²⁷Mg	²⁰Mg
13	²⁸Al
14	²⁹Si
15	³⁰P
16	³¹S
17	³²Cl
18	³³Ar
19	³⁴K
20	³⁵Ca
21	³⁶Sc