Master Isotope Table — Known vs Predicted (Z =

This ledger shows for each element:

Known isotopes(experimentally observed)
Stable (strict)isotopes (per IUPAC; ultra-long-lived treated as radioactive)
Unstable isotopes(= Known − Stable)
Predicted isotopes(scaled to Neufcourt et al. 2020 central estimate: 7,759 total bound nuclides)
Gap(Predicted − Known)

Totals

Total elements: 118
Known isotopes: 3,269
Stable isotopes (strict): 273
Unstable isotopes: 2,996
Predicted isotopes: 7,759
Total Gap: 4,490
Scale factor: 2.373509

Table (Z = 1–118)

Z	Element	Known	Stable (strict)	Unstable	Predicted (est.)	Gap
1	H	7	2	5	17	10
2	He	9	2	7	21	12
3	Li	11	2	9	26	15
4	Be	12	1	11	28	16
5	B	13	2	11	31	18
6	C	15	2	13	36	21
7	N	16	2	14	38	22
8	O	17	3	14	40	23
9	F	18	1	17	43	25
10	Ne	19	3	16	45	26
11	Na	20	1	19	47	27
12	Mg	22	3	19	52	30
13	Al	22	1	21	52	30
14	Si	23	3	20	55	32
15	P	23	1	22	55	32
16	S	24	4	20	57	33
17	Cl	24	2	22	57	33
18	Ar	24	3	21	57	33
19	K	24	2	22	57	33
20	Ca	24	6	18	57	33
21	Sc	25	1	24	59	34
22	Ti	26	5	21	62	36
23	V	26	1	25	62	36
24	Cr	26	4	22	62	36
25	Mn	26	1	25	62	36
26	Fe	28	4	24	66	38
27	Co	29	1	28	69	40
28	Ni	31	5	26	74	43
29	Cu	29	2	27	69	40
30	Zn	30	5	25	71	41
31	Ga	31	2	29	74	43
32	Ge	32	5	27	76	44
33	As	33	1	32	78	45
34	Se	30	6	24	71	41
35	Br	31	2	29	74	43
36	Kr	32	6	26	76	44
37	Rb	32	1	31	76	44
38	Sr	34	4	30	81	47
39	Y	32	1	31	76	44
40	Zr	34	5	29	81	47
41	Nb	34	1	33	81	47
42	Mo	35	7	28	83	48
43	Tc	36	0	36	85	49
44	Ru	37	7	30	88	51
45	Rh	35	1	34	83	48
46	Pd	36	6	30	85	49
47	Ag	38	2	36	90	52
48	Cd	39	8	31	93	54
49	In	39	2	37	93	54
50	Sn	40	10	30	95	55
51	Sb	36	2	34	85	49
52	Te	38	8	30	90	52
53	I	37	1	36	88	51
54	Xe	40	9	31	95	55
55	Cs	39	1	38	93	54
56	Ba	40	7	33	95	55
57	La	39	1	38	93	54
58	Ce	40	4	36	95	55
59	Pr	39	1	38	93	54
60	Nd	41	5	36	97	56
61	Pm	39	0	39	93	54
62	Sm	41	7	34	97	56
63	Eu	40	2	38	95	55
64	Gd	41	7	34	97	56
65	Tb	39	1	38	93	54
66	Dy	40	7	33	95	55
67	Ho	39	1	38	93	54
68	Er	40	6	34	95	55
69	Tm	39	1	38	93	54
70	Yb	41	7	34	97	56
71	Lu	40	1	39	95	55
72	Hf	36	5	31	85	49
73	Ta	37	1	36	88	51
74	W	35	5	30	83	48
75	Re	39	1	38	93	54
76	Os	35	7	28	83	48
77	Ir	34	2	32	81	47
78	Pt	35	6	29	83	48
79	Au	36	1	35	85	49
80	Hg	38	7	31	90	52
81	Tl	39	2	37	93	54
82	Pb	43	4	39	102	59
83	Bi	41	0	41	97	56
84	Po	42	0	42	100	58
85	At	39	0	39	93	54
86	Rn	39	0	39	93	54
87	Fr	34	0	34	81	47
88	Ra	34	0	34	81	47
89	Ac	33	0	33	78	45
90	Th	31	1	30	74	43
91	Pa	29	0	29	69	40
92	U	28	0	28	66	38
93	Np	20	0	20	47	27
94	Pu	20	0	20	47	27
95	Am	17	0	17	40	23
96	Cm	19	0	19	45	26
97	Bk	21	0	21	50	29
98	Cf	20	0	20	47	27
99	Es	18	0	18	43	25
100	Fm	19	0	19	45	26
101	Md	16	0	16	38	22
102	No	13	0	13	31	18
103	Lr	16	0	16	38	22
104	Rf	18	0	18	43	25
105	Db	16	0	16	38	22
106	Sg	14	0	14	33	19
107	Bh	15	0	15	36	21
108	Hs	15	0	15	36	21
109	Mt	13	0	13	31	18
110	Ds	15	0	15	36	21
111	Rg	11	0	11	26	15
112	Cn	9	0	9	21	12
113	Nh	9	0	9	21	12
114	Fl	6	0	6	14	8
115	Mc	4	0	4	9	5
116	Lv	4	0	4	9	5
117	Ts	2	0	2	5	3
118	Og	1	0	1	2	1

Method: Predictions are scaled per element so that the global sum matches 7,759 predicted isotopes. Source reference: Neufcourt et al., 2020.

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