Isotopes of tellurium
List of isotopes
Bold for isotopes with half-lives longer than the age of the universe (nearly stable) Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes Believed to undergo β⁺β⁺ decay to ¹²⁰Sn with a half-life over 2.2×10¹⁶ years Believed to undergo β⁺ decay to ¹²³Sb with a half-life over 9.2×10¹⁶ years Fission product Primordial radionuclide Longest measured half-life of any nuclide Very short-lived fission product, responsible for the iodine pit as precursor of ¹³⁵Xe via ¹³⁵I

Isotopes of tellurium

Section Title: List of isotopes
Table Section Text: Bold for isotopes with half-lives longer than the age of the universe (nearly stable) Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes Believed to undergo β⁺β⁺ decay to ¹²⁰Sn with a half-life over 2.2×10¹⁶ years Believed to undergo β⁺ decay to ¹²³Sb with a half-life over 9.2×10¹⁶ years Fission product Primordial radionuclide Longest measured half-life of any nuclide Very short-lived fission product, responsible for the iodine pit as precursor of ¹³⁵Xe via ¹³⁵I

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)	daughter isotope(s)	nuclear spin and parity	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)

excitation energy

104Te	52	52	<18 ns	α	100Sn	0+

105Te	52	53	104.94364(54)#	620(70) ns	α	101Sn	5/2+#

106Te	52	54	105.93750(14)	70(20) µs [70(+20−10) µs]	α	102Sn	0+

107Te	52	55	106.93501(32)#	3.1(1) ms	α (70%)	103Sn	5/2+#

β+ (30%)	107Sb

108Te	52	56	107.92944(11)	2.1(1) s	α (49%)	104Sn	0+

β+ (48.5%)	108Sb

β+, p (2.4%)	107Sn

β+, α (.065%)	104In

109Te	52	57	108.92742(7)	4.6(3) s	β+ (86.99%)	109Sb	(5/2+)

β+, p (9.4%)	108Sn

α (7.9%)	105Sn

β+, α (.005%)	105In

110Te	52	58	109.92241(6)	18.6(8) s	β+ (99.99%)	110Sb	0+

β+, p (.003%)	109Sn

111Te	52	59	110.92111(8)	19.3(4) s	β+	111Sb	(5/2)+#

β+, p (rare)	110Sn

112Te	52	60	111.91701(18)	2.0(2) min	β+	112Sb	0+

113Te	52	61	112.91589(3)	1.7(2) min	β+	113Sb	(7/2+)

114Te	52	62	113.91209(3)	15.2(7) min	β+	114Sb	0+

115Te	52	63	114.91190(3)	5.8(2) min	β+	115Sb	7/2+

115m1Te	10(7) keV	6.7(4) min	β+	115Sb	(1/2)+

IT	115Te

115m2Te	280.05(20) keV	7.5(2) µs	11/2−

116Te	52	64	115.90846(3)	2.49(4) h	β+	116Sb	0+

117Te	52	65	116.908645(14)	62(2) min	β+	117Sb	1/2+

117mTe	296.1(5) keV	103(3) ms	IT	117Te	(11/2−)

118Te	52	66	117.905828(16)	6.00(2) d	EC	118Sb	0+

119Te	52	67	118.906404(9)	16.05(5) h	β+	119Sb	1/2+

119mTe	260.96(5) keV	4.70(4) d	β+ (99.99%)	119Sb	11/2−

IT (.008%)	119Te

120Te	52	68	119.90402(1)	Observationally Stable	0+	9(1)×10−4

121Te	52	69	120.904936(28)	19.16(5) d	β+	121Sb	1/2+

121mTe	293.991(22) keV	154(7) d	IT (88.6%)	121Te	11/2−

β+ (11.4%)	121Sb

122Te	52	70	121.9030439(16)	Stable	0+	0.0255(12)

123Te	52	71	122.9042700(16)	Observationally Stable	1/2+	0.0089(3)

123mTe	247.47(4) keV	119.2(1) d	IT	123Te	11/2−

124Te	52	72	123.9028179(16)	Stable	0+	0.0474(14)

125Te	52	73	124.9044307(16)	Stable	1/2+	0.0707(15)

125mTe	144.772(9) keV	57.40(15) d	IT	125Te	11/2−

126Te	52	74	125.9033117(16)	Stable	0+	0.1884(25)

127Te	52	75	126.9052263(16)	9.35(7) h	β−	127I	3/2+

127mTe	88.26(8) keV	109(2) d	IT (97.6%)	127Te	11/2−

β− (2.4%)	127I

128Te	52	76	127.9044631(19)	2.2(3)×1024 y	β−β−	128Xe	0+	0.3174(8)

128mTe	2790.7(4) keV	370(30) ns	10+

129Te	52	77	128.9065982(19)	69.6(3) min	β−	129I	3/2+

129mTe	105.50(5) keV	33.6(1) d	11/2-

130Te	52	78	129.9062244(21)	8.2(0.2 (stat.), 0.6 (syst.))×1020 y	β−β−	130Xe	0+	0.3408(62)

130m1Te	2146.41(4) keV	115(8) ns	(7)−

130m2Te	2661(7) keV	1.90(8) µs	(10+)

130m3Te	4375.4(18) keV	261(33) ns

131Te	52	79	130.9085239(21)	25.0(1) min	β−	131I	3/2+

131mTe	182.250(20) keV	30(2) h	β− (77.8%)	131I	11/2−

IT (22.2%)	131Te

132Te	52	80	131.908553(7)	3.204(13) d	β−	132I	0+

133Te	52	81	132.910955(26)	12.5(3) min	β−	133I	(3/2+)

133mTe	334.26(4) keV	55.4(4) min	β− (82.5%)	133I	(11/2−)

IT (17.5%)	133Te

134Te	52	82	133.911369(11)	41.8(8) min	β−	134I	0+

134mTe	1691.34(16) keV	164.1(9) ns	6+

135Te	52	83	134.91645(10)	19.0(2) s	β−	135I	(7/2-)

135mTe	1554.88(17) keV	510(20) ns	(19/2−)

136Te	52	84	135.92010(5)	17.63(8) s	β− (98.7%)	136I	0+

β−, n (1.3%)	135I

137Te	52	85	136.92532(13)	2.49(5) s	β− (97.01%)	137I	3/2−#

β−, n (2.99%)	136I

138Te	52	86	137.92922(22)#	1.4(4) s	β− (93.7%)	138I	0+

β−, n (6.3%)	137I

139Te	52	87	138.93473(43)#	500 ms [>300 ns]#	β−	139I	5/2−#

β−, n	138I

140Te	52	88	139.93885(32)#	300 ms [>300 ns]#	β−	140I	0+

β−, n	139I

141Te	52	89	140.94465(43)#	100 ms [>300 ns]#	β−	141I	5/2−#

β−, n	140I

142Te	52	90	141.94908(64)#	50 ms [>300 ns]#	β−	142I	0+

Sentence(s)

The longest-lived isotope of tellurium is ¹²¹Te with a half-life of nearly 19 days.

final_sentence: The longest-lived isotope of tellurium is ¹²¹Te with a half-life of nearly 19 days.