Periodic Table/Americium/²⁴⁰Am

← 239Am241Am →

²⁴⁰Am

Americium-240

Radioactive· Half-life: 2.12 d

Nuclear Propertiesbinding energy · spin-parity · abundance

Protons (Z)

95

Neutrons (N)

145

Mass Number (A)

240

Atomic Mass

240.055298AMU

Spin / Parity

3-

Binding E/A

7.345keV

Natural Abundance

Trace / None

Half-life

2.12 d

Decay Modesoverview · half-life · α · β⁻ · β⁺

β⁺

100.0%

α

1.9%

Decay Chain

²⁴⁰AmAmericium2.12 d

β⁺100.0%

α²³⁶Np1.90%

²⁴⁰PuPlutonium6.56 ky

α100.0%

34Si²⁰⁶Hg1.30%

²³⁶UUranium23.4 My

α100.0%

²³²ThThorium14.0 Gy

α100.0%

26Ne²⁰⁶Hg2.78%

2β⁻²³²U

²²⁸RaRadium5.75 y

β⁻100.0%

²²⁸AcActinium6.15 h

β⁻100.0%

²²⁸ThThorium1.91 y

α100.0%

20O²⁰⁸Pb1.13%

²²⁴RaRadium3.63 d

α100.0%

¹⁴C²¹⁰Pb4.00%

²²⁰RnRadon55.6 s

α100.0%

2β⁻²²⁰Ra

²¹⁶PoPolonium144 ms

α100.0%

2β⁻²¹⁶Rn

²¹²PbLead10.6 h

β⁻100.0%

²¹²BiBismuth1.01 h

β⁻64.1%

α²⁰⁸Tl35.9%

β⁻α²⁰⁸Pb0.01%

²¹²PoPolonium294 ns

α100.0%

²⁰⁸PbLeadSTABLE

14-step decay chain → stable · Primary path shown · branching ratios indicated

Other Isotopes of Americium

223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249

← Back to AmericiumData: IAEA NDS · ENSDF