Technetium-109

Properties and data of the isotope ¹⁰⁹Tc.

Contents

General data

Name of the isotope:Technetium-109; Tc-109Symbol:¹⁰⁹Tc or 10943TcMass number A:109 (= number of nucleons)Atomic number Z:43 (= number of protons)Neutrons N:66Isotopic mass:108.920254(10) u (atomic weight of Technetium-109)Nuclide mass:108.8966662 u (calculated nuclear mass without electrons)Mass excess:-74.28292 MeVMass defect:0.988106832 u (per nucleus)Nuclear binding energy:920.41558537 MeV (per nucleus)
8.44417968 MeV (average binding energy per nucleon)Separation energy:S_N = 6.431(13) MeV (first neutron)
S_P = 10.816(13) MeV (first proton)Half-life:0.91(3) sDecay constant λ:0.76170019841752 s^-1Specific activity α:4.247283229548 × 10⁺²¹ Bq g^-1
114791438636.44 Ci g^-1Spin and parity:
(nuclear angular momentum)(5/2+)Year of discovery:1976

Radioactive Decay

Half-life T_½ = 0.91(3) s respectively 9.1 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁰⁹Ru	< 100 %	6.456(13) MeV
β^-, n	¹⁰⁸Ru	0.08(2) %	1.307(12) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 66) and isobaric (same nucleon number A = 109) with Technetium-109. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 66	Isobar A = 109
37	¹⁰³Rb
38	¹⁰⁴Sr
39	¹⁰⁵Y	¹⁰⁹Y
40	¹⁰⁶Zr	¹⁰⁹Zr
41	¹⁰⁷Nb	¹⁰⁹Nb
42	¹⁰⁸Mo	¹⁰⁹Mo
43	¹⁰⁹Tc	¹⁰⁹Tc
44	¹¹⁰Ru	¹⁰⁹Ru
45	¹¹¹Rh	¹⁰⁹Rh
46	¹¹²Pd	¹⁰⁹Pd
47	¹¹³Ag	¹⁰⁹Ag
48	¹¹⁴Cd	¹⁰⁹Cd
49	¹¹⁵In	¹⁰⁹In
50	¹¹⁶Sn	¹⁰⁹Sn
51	¹¹⁷Sb	¹⁰⁹Sb
52	¹¹⁸Te	¹⁰⁹Te
53	¹¹⁹I	¹⁰⁹I
54	¹²⁰Xe	¹⁰⁹Xe
55	¹²¹Cs
56	¹²²Ba
57	¹²³La
58	¹²⁴Ce
59	¹²⁵Pr
60	¹²⁶Nd
61	¹²⁷Pm
62	¹²⁸Sm