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isotope, among two or even more species of atoms of a chemical element via the very same atomic number and place in the regular table and virtually the same chemical behaviour but through different atomic masses and also physical properties. Eextremely chemical aspect has actually one or even more isotopes.
An atom is initially established and also labeled according to the variety of protons in its nucleus. This atomic number is ordinarily offered the symbol Z. The excellent prestige of the atomic number derives from the observation that all atoms via the same atomic number have actually practically, if not specifically, the same chemical properties. A big arsenal of atoms via the same atomic number constitutes a sample of an element. A bar of pure uranium, for instance, would certainly consist completely of atoms via atomic number 92. The routine table of the elements asindications one area to eincredibly atomic number, and also each of these places is labeled via the common name of the facet, as, for example, calcium, radon, or uranium.
Not all the atoms of an facet require have the exact same variety of neutrons in their nuclei. In fact, it is specifically the variation in the variety of neutrons in the nuclei of atoms that provides increase to isotopes. Hydrogen is a instance in suggest. It has the atomic number 1. Three nuclei via one proton are well-known that contain 0, 1, and also 2 neutrons, respectively. The three share the location in the periodic table assigned to atomic number 1 and also thus are referred to as isotopes (from the Greek isos, meaning “very same,” and also topos, signifying “place”) of hydrogen.
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Many vital properties of an isotope depfinish on its mass. The total variety of neutrons and protons (symbol A), or mass number, of the nucleus offers roughly the mass measured on the so-called atomic-mass-unit (amu) scale. The numerical distinction in between the actual measured mass of an isotope and A is referred to as either the mass excess or the mass defect (symbol Δ; see table).
Sources: G. Audi and also A.H. Wapstra, "The 1995 Update to Atomic Mass Evaluation," Nuclear Physics, A595:409–480 (1995); K.J.R. Rosguy and P.D.P. Taylor, "Isotopic Compositions of the Elements 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 | He | 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 | Be | 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 | P | 31 | 100 | −24.441 |
sulhair | 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 |
iron | 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 | As | 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 | Te | 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 | |||
gold | 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 | |||
lead | 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 |