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Key People:Francis wilhelm AstonFrederick SoddyTheodore wilhelm Richards...(Show more)Related Topics:DeuteriumRadioactive isotopeTritiumTantalum-180Tantalum-181...(Show more)

isotope, among two or much more species of atoms of a chemical aspect with the same atomic number and position in the routine table and practically identical chemical behaviour but with different atomic masses and also physical properties. Every chemical element has one or an ext isotopes.
An atom is very first identified and labeled according to the variety of protons in that nucleus. This atomic number is ordinarily provided the price Z. The an excellent importance of the atom number derives native the observation that all atoms with the very same atomic number have nearly, if not precisely, identical chemical properties. A huge collection of atoms v the same atomic number constitutes a sample of one element. A bar the pure uranium, for instance, would certainly consist completely of atoms through atomic number 92. The routine table the the elements assigns one ar to every atomic number, and also each of these places is labeled v the usual name of the element, as, because that example, calcium, radon, or uranium.
Not every the atoms of an element need have actually the same number of neutrons in their nuclei. In fact, that is specifically the sports in the number of neutrons in the nuclei of atom that gives rise to isotopes. Hydrogen is a case in point. It has actually the atom number 1. Three nuclei through one proton are known that contain 0, 1, and 2 neutrons, respectively. The 3 share the ar in the regular table assigned to atomic number 1 and also hence are called isotopes (from the Greek isos, meaning “same,” and topos, signifying “place”) of hydrogen.
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Many vital properties of one isotope depend on that is mass. The total number of neutrons and protons (symbol A), or mass number, the the cell core gives about the fixed measured ~ above the so-called atomic-mass-unit (amu) scale. The numerical difference in between the actual measured fixed of one isotope and A is referred to as either the fixed excess or the massive defect (symbol Δ; see table).
Sources: G. Audi and A.H. Wapstra, "The 1995 upgrade to atom Mass Evaluation," nuclear Physics, A595:409–480 (1995); K.J.R. Rosman and also P.D.P. Taylor, "Isotopic Compositions that the facets 1997," J. Phys. Chem. Ref. Data, 27:1275–85 (1995). | |||||
hydrogen | 1 | H | 1 | 99.9885 | 7.289 |
2 | 0.0151 | 13.136 | |||
helium | 2 | the | 3 | 0.000138 | 14.931 |
4 | 99.999863 | 2.425 | |||
lithium | 3 | Li | 6 | 7.59 | 14.086 |
7 | 92.41 | 14.908 | |||
beryllium | 4 | it is in | 9 | 100 | 11.348 |
boron | 5 | B | 10 | 19.9 | 12.051 |
11 | 80.1 | 8.668 | |||
carbon | 6 | C | 12 | 98.93 | 0 |
13 | 1.07 | 3.125 | |||
nitrogen | 7 | N | 14 | 99.632 | 2.863 |
15 | 0.368 | 0.101 | |||
oxygen | 8 | O | 16 | 99.757 | −4.737 |
17 | 0.038 | −0.809 | |||
18 | 0.205 | −0.782 | |||
fluorine | 9 | F | 19 | 100 | −1.487 |
neon | 10 | Ne | 20 | 90.48 | −7.042 |
21 | 0.27 | −5.732 | |||
22 | 9.25 | −8.024 | |||
sodium | 11 | Na | 23 | 100 | −9.529 |
magnesium | 12 | Mg | 24 | 78.99 | −13.933 |
25 | 10.00 | −13.193 | |||
26 | 11.01 | −16.214 | |||
aluminum | 13 | Al | 27 | 100 | −17.197 |
silicon | 14 | Si | 28 | 92.2297 | −21.493 |
29 | 4.6832 | −21.895 | |||
30 | 3.0872 | −24.433 | |||
phosphorus | 15 | ns | 31 | 100 | −24.441 |
sulfur | 16 | S | 32 | 94.93 | −26.016 |
33 | 0.76 | −26.586 | |||
34 | 4.29 | −29.932 | |||
36 | 0.02 | −30.664 | |||
chlorine | 17 | Cl | 35 | 75.78 | −29.014 |
37 | 24.22 | −31.762 | |||
argon | 18 | Ar | 36 | 0.3365 | −30.230 |
38 | 0.0632 | −34.715 | |||
40 | 99.6003 | −35.040 | |||
potassium | 19 | K | 39 | 93.2581 | −33.807 |
40 | 0.0117 | −33.535 | |||
41 | 6.7302 | −35.559 | |||
calcium | 20 | Ca | 40 | 96.941 | −34.846 |
42 | 0.647 | −38.547 | |||
43 | 0.135 | −38.408 | |||
44 | 2.086 | −41.469 | |||
46 | 0.004 | −43.135 | |||
48 | 0.187 | −44.215 | |||
scandium | 21 | Sc | 45 | 100 | −41.069 |
titanium | 22 | Ti | 46 | 8.25 | −44.125 |
47 | 7.44 | −44.932 | |||
48 | 73.72 | −48.487 | |||
49 | 5.41 | −48.558 | |||
50 | 5.18 | −51.426 | |||
vanadium | 23 | V | 50 | 0.250 | −49.218 |
51 | 99.750 | −52.198 | |||
chromium | 24 | Cr | 50 | 4.345 | −50.254 |
52 | 83.789 | −55.413 | |||
53 | 9.501 | −55.281 | |||
54 | 2.365 | −56.928 | |||
manganese | 25 | Mn | 55 | 100 | −57.706 |
steel | 26 | Fe | 54 | 5.845 | −56.248 |
56 | 91.754 | −60.601 | |||
57 | 2.119 | −60.176 | |||
58 | 0.282 | −62.149 | |||
cobalt | 27 | Co | 59 | 100 | −62.224 |
nickel | 28 | Ni | 58 | 68.0769 | −60.223 |
60 | 26.2231 | −64.468 | |||
61 | 1.1399 | −64.217 | |||
62 | 3.6345 | −66.743 | |||
64 | 0.9256 | −67.096 | |||
copper | 29 | Cu | 63 | 69.17 | −65.576 |
65 | 30.83 | −67.260 | |||
zinc | 30 | Zn | 64 | 48.63 | −66.000 |
66 | 27.90 | −68.896 | |||
67 | 4.10 | −67.877 | |||
68 | 18.75 | −70.004 | |||
70 | 0.62 | −69.559 | |||
gallium | 31 | Ga | 69 | 60.108 | −69.321 |
71 | 39.892 | −70.137 | |||
germanium | 32 | Ge | 70 | 20.84 | −70.560 |
72 | 27.54 | −72.586 | |||
73 | 7.73 | −71.299 | |||
74 | 36.28 | −73.422 | |||
76 | 7.61 | −73.213 | |||
arsenic | 33 | together | 75 | 100 | −73.032 |
selenium | 34 | Se | 74 | 0.89 | −72.213 |
76 | 9.37 | −75.252 | |||
77 | 7.63 | −74.599 | |||
78 | 23.77 | −77.026 | |||
80 | 49.61 | −77.759 | |||
82 | 8.73 | −77.593 | |||
bromine | 35 | Br | 79 | 50.69 | −76.068 |
81 | 49.31 | −77.974 | |||
krypton | 36 | Kr | 78 | 0.35 | −74.160 |
80 | 2.28 | −77.893 | |||
82 | 11.58 | −80.589 | |||
83 | 11.49 | −79.982 | |||
84 | 57.00 | −82.431 | |||
86 | 17.30 | −83.266 | |||
rubidium | 37 | Rb | 85 | 72.17 | −82.168 |
87 | 27.83 | −84.595 | |||
strontium | 38 | Sr | 84 | 0.56 | −80.644 |
86 | 9.86 | −84.522 | |||
87 | 7.00 | −84.878 | |||
88 | 82.58 | −87.920 | |||
yttrium | 39 | Y | 89 | 100 | −87.702 |
zirconium | 40 | Zr | 90 | 51.45 | −88.768 |
91 | 11.22 | −87.891 | |||
92 | 17.15 | −88.455 | |||
94 | 17.38 | −87.266 | |||
96 | 2.80 | −85.441 | |||
niobium | 41 | Nb | 93 | 100 | −87.209 |
molybdenum | 42 | Mo | 92 | 14.84 | −86.805 |
94 | 9.25 | −88.410 | |||
95 | 15.92 | −87.708 | |||
96 | 16.68 | −88.791 | |||
97 | 9.55 | −87.541 | |||
98 | 24.13 | −88.112 | |||
100 | 9.63 | −86.184 | |||
ruthenium | 44 | Ru | 96 | 5.54 | −86.072 |
98 | 1.87 | −88.224 | |||
99 | 12.76 | −87.617 | |||
100 | 12.60 | −89.219 | |||
101 | 17.06 | −87.950 | |||
102 | 31.55 | −89.098 | |||
104 | 18.62 | −88.091 | |||
rhodium | 45 | Rh | 103 | 100 | −88.022 |
palladium | 46 | Pd | 102 | 1.020 | −87.926 |
104 | 11.14 | −89.391 | |||
105 | 22.33 | −88.414 | |||
106 | 27.33 | −89.905 | |||
108 | 26.46 | −89.522 | |||
110 | 11.72 | −88.350 | |||
silver- | 47 | Ag | 107 | 51.8392 | −88.405 |
109 | 48.1608 | −88.720 | |||
cadmium | 48 | Cd | 106 | 1.25 | −87.134 |
108 | 0.89 | −89.253 | |||
110 | 12.49 | −90.350 | |||
111 | 12.80 | −89.254 | |||
112 | 24.13 | −90.581 | |||
113 | 12.22 | −89.050 | |||
114 | 28.73 | −90.021 | |||
116 | 7.49 | −88.720 | |||
indium | 49 | In | 113 | 4.288 | −89.366 |
115 | 95.712 | −89.537 | |||
tin | 50 | Sn | 112 | 0.973 | −88.659 |
114 | 0.659 | −90.558 | |||
115 | 0.339 | −90.033 | |||
116 | 14.536 | −91.525 | |||
117 | 7.676 | −90.398 | |||
118 | 24.223 | −91.653 | |||
119 | 8.585 | −90.067 | |||
120 | 32.593 | −91.103 | |||
122 | 4.629 | −89.944 | |||
124 | 5.789 | −88.236 | |||
antimony | 51 | Sb | 121 | 57.213 | −89.593 |
123 | 42.787 | −89.222 | |||
tellurium | 52 | dare | 120 | 0.096 | −89.405 |
122 | 2.603 | −90.311 | |||
123 | 0.908 | −89.169 | |||
124 | 4.816 | −90.523 | |||
125 | 7.139 | −89.028 | |||
126 | 18.952 | −90.070 | |||
128 | 31.687 | −88.994 | |||
130 | 33.799 | −87.353 | |||
iodine | 53 | i | 127 | 100 | −88.987 |
xenon | 54 | Xe | 124 | 0.08913 | −87.658 |
126 | 0.08880 | −89.173 | |||
128 | 1.91732 | −89.861 | |||
129 | 26.43964 | −89.697 | |||
130 | 4.08271 | −89.881 | |||
131 | 21.17961 | −88.416 | |||
132 | 26.89157 | −89.280 | |||
134 | 10.44232 | −88.124 | |||
136 | 8.86590 | −86.424 | |||
cesium | 55 | Cs | 133 | 100 | −88.076 |
barium | 56 | Ba | 130 | 0.1058 | −87.271 |
132 | 0.1012 | −88.440 | |||
134 | 2.417 | −88.954 | |||
135 | 6.592 | −87.856 | |||
136 | 7.853 | −88.892 | |||
137 | 11.232 | −87.727 | |||
138 | 71.699 | −88.267 | |||
lanthanum | 57 | La | 138 | 0.09017 | −86.529 |
139 | 99.91 | −87.236 | |||
cerium | 58 | Ce | 136 | 0.186 | −86.500 |
138 | 0.251 | −87.574 | |||
140 | 88.449 | −88.088 | |||
142 | 11.114 | −84.543 | |||
praseodymium | 59 | Pr | 141 | 100 | −86.026 |
neodymium | 60 | Nd | 142 | 27.16 | −85.960 |
143 | 12.18 | −84.012 | |||
144 | 23.83 | −83.758 | |||
145 | 8.30 | −81.442 | |||
146 | 17.17 | −80.936 | |||
148 | 5.74 | −77.418 | |||
150 | 5.62 | −73.694 | |||
samarium | 62 | Sm | 144 | 3.0734 | −81.976 |
147 | 14.9934 | −79.276 | |||
148 | 11.2406 | −79.347 | |||
149 | 13.8189 | −77.147 | |||
150 | 7.3796 | −77.061 | |||
152 | 26.7421 | −74.773 | |||
154 | 22.7520 | −72.465 | |||
europium | 63 | Eu | 151 | 47.810 | −74.663 |
153 | 52.190 | −73.377 | |||
gadolinium | 64 | Gd | 152 | 0.2029 | −74.717 |
154 | 2.1809 | −73.716 | |||
155 | 14.7998 | −72.080 | |||
156 | 20.4664 | −72.545 | |||
157 | 15.6518 | −70.834 | |||
158 | 24.8347 | −0.700 | |||
160 | 21.8635 | −67.952 | |||
terbium | 65 | Tb | 159 | 100 | −69.542 |
dysprosium | 66 | Dy | 156 | 0.056 | −70.534 |
158 | 0.096 | −70.417 | |||
160 | 2.34 | −69.682 | |||
161 | 18.91 | −68.065 | |||
162 | 25.51 | −68.190 | |||
163 | 24.90 | −66.390 | |||
164 | 28.19 | −65.977 | |||
holmium | 67 | Ho | 165 | 100 | −64.907 |
erbium | 68 | Er | 162 | 0.137 | −66.346 |
164 | 1.609 | −65.953 | |||
166 | 33.61 | −64.934 | |||
167 | 22.93 | −63.299 | |||
168 | 26.79 | −62.999 | |||
170 | 14.93 | −60.118 | |||
thulium | 69 | Tm | 169 | 100 | −61.282 |
ytterbium | 70 | Yb | 168 | 0.127 | −61.577 |
170 | 3.04 | −60.772 | |||
171 | 14.28 | −59.315 | |||
172 | 21.83 | −59.264 | |||
173 | 16.13 | −57.560 | |||
174 | 31.83 | −56.953 | |||
176 | 12.76 | −53.497 | |||
lutetium | 71 | Lu | 175 | 97.416 | −55.174 |
176 | 2.584 | −53.391 | |||
hafnium | 72 | Hf | 174 | 0.1620 | −55.852 |
176 | 5.604 | −54.584 | |||
177 | 18.5953 | −52.890 | |||
178 | 27.811 | −52.445 | |||
179 | 13.6210 | −50.473 | |||
180 | 35.0802 | −49.790 | |||
tantalum | 73 | Ta | 180 | 0.0123 | −48.935 |
181 | 99.9877 | −48.441 | |||
tungsten | 74 | W | 180 | 0.1198 | −49.643 |
182 | 26.4985 | −48.246 | |||
183 | 14.3136 | −46.366 | |||
184 | 30.6422 | −45.706 | |||
186 | 28.4259 | −42.511 | |||
rhenium | 75 | Re | 185 | 37.398 | −43.821 |
187 | 62.602 | −41.218 | |||
osmium | 76 | Os | 184 | 0.0197 | −44.254 |
186 | 1.5859 | −42.999 | |||
187 | 1.9644 | −41.220 | |||
188 | 13.2434 | −41.138 | |||
189 | 16.1466 | −38.988 | |||
190 | 26.2584 | −38.708 | |||
192 | 40.7815 | −35.882 | |||
iridium | 77 | Ir | 191 | 37.272 | −36.709 |
193 | 62.728 | −34.536 | |||
platinum | 78 | Pt | 190 | 0.013634 | −37.325 |
192 | 0.782659 | −36.296 | |||
194 | 32.96700 | −34.779 | |||
195 | 33.831557 | −32.812 | |||
196 | 25.24166 | −32.663 | |||
198 | 7.16349 | −29.923 | |||
yellow | 79 | Au | 197 | 100 | −31.157 |
mercury | 80 | Hg | 196 | 0.15344 | −31.843 |
198 | 9.968 | −30.970 | |||
199 | 16.873 | −29.563 | |||
200 | 23.096 | −29.520 | |||
201 | 13.181 | −27.679 | |||
202 | 29.863 | −27.362 | |||
204 | 6.865 | −24.707 | |||
thallium | 81 | Tl | 203 | 29.524 | −25.775 |
205 | 70.476 | −23.834 | |||
command | 82 | Pb | 204 | 1.4245 | −25.123 |
206 | 24.1447 | −23.801 | |||
207 | 22.0827 | −22.467 | |||
208 | 52.3481 | −21.764 | |||
bismuth | 83 | Bi | 209 | 100 | −18.273 |
thorium | 90 | Th | 232 | 100 | 35.444 |
uranium | 92 | U | 234 | 0.00548 | 38.141 |
235 | 0.7200 | 40.914 | |||
238 | 99.2745 | 47.304 |