鈉（原子量：22.98976928(2)）共有22個已知同位素，質量數介於18-37之間，其中只有1個是穩定的，其他都具有放射性，因此鈉屬於單一同位素元素。天然存在的鈉同位素有3個，分別是穩定的23Na和具放射性的22Na及24Na，其中23Na占天然鈉的絕大部分，而22Na和24Na在自然界中僅痕量存在，為宇宙射線散裂所產生。其他放射性同位素都不出現在自然界中，只有在實驗室製造出來過，且半衰期都極短，非常不穩定。
Quick Facts 同位素, 衰變 ...
主要的鈉同位素|
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| 標準原子質量 (Ar, 標準) | - 7001229897692800000♠22.98976928(2)[1]
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Close
More information 符號, Z ...
| 符號
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Z
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N
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同位素質量（u）
[n 1][n 2]
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半衰期
[n 1][n 2]
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衰變
方式[2]
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衰變
產物
[n 3]
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原子核
自旋[n 1]
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相對豐度
（莫耳分率）
|
18
Na
|
11
|
7
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7001180259700000000♠18.02597(5)
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6979129999999999999♠1.3(4)×10−21 s
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p (>99.9%)
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17Ne
|
(1−)#
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| β+ (<.1%)
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18Ne
|
19
Na
|
11
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8
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7001190138770000000♠19.013877(13)
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<40 ns
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p
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18Ne
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(5/2+)#
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20
Na
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11
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9
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7001200073510000000♠20.007351(7)
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447.9(23) ms
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β+ (75%)
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20Ne
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2+
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| β+, α (25%)
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16O
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21
Na
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11
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10
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7001209976552000000♠20.9976552(8)
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22.49(4) s
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β+
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21Ne
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3/2+
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22
Na
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11
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11
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7001219944364000000♠21.9944364(4)
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2.6027(10) y
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β+
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22Ne
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3+
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痕量[n 4]
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22m
Na
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583.03(9) keV
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244(6) ns
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|
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1+
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23
Na
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11
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12
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7001229897692809000♠22.9897692809(29)
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穩定
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3/2+
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7000100000000000000♠1.0000
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24
Na
|
11
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13
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7001239909627800000♠23.99096278(8)
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7004538524000000000♠14.9590(12) h
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β−
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24Mg
|
4+
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痕量[n 4]
|
24m
Na
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472.207(9) keV
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20.20(7) ms
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IT (99.95%)
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24Na
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1+
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| β− (.05%)
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24Mg
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25
Na
|
11
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14
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7001249899540000000♠24.9899540(13)
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59.1(6) s
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β−
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25Mg
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5/2+
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26
Na
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11
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15
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7001259926330000000♠25.992633(6)
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1.077(5) s
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β−
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26Mg
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3+
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27
Na
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11
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16
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7001269940770000000♠26.994077(4)
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301(6) ms
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β− (99.87%)
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27Mg
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5/2+
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| β−, n (.13%)
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26Mg
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28
Na
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11
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17
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7001279989380000000♠27.998938(14)
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30.5(4) ms
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β− (99.421%)
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28Mg
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1+
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| β−, n (.579%)
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27Mg
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29
Na
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11
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18
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7001290028610000000♠29.002861(14)
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44.9(12) ms
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β− (74.09%)
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29Mg
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3/2(+#)
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| β−, n (25.91%)
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28Mg
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30
Na
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11
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19
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7001300089760000000♠30.008976(27)
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48.4(17) ms
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β− (68.83%)
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30Mg
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2+
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| β−, n (30.0%)
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29Mg
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| β−, 2n (1.17%)
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28Mg
|
| β−, α
|
26Ne
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31
Na
|
11
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20
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7001310135900000000♠31.01359(23)
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17.0(4) ms
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β− (62.05%)
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31Mg
|
(3/2+)
|
|
| β−, n
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30Mg
|
| β−, 2n
|
29Mg
|
| β−, 3n
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28Mg
|
32
Na
|
11
|
21
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7001320204700000000♠32.02047(38)
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12.9(7) ms
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β−
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32Mg
|
(3−,4−)
|
|
| β−, n
|
31Mg
|
| β−, 2n
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30Mg
|
33
Na
|
11
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22
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7001330267200000000♠33.02672(94)
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8.2(2) ms
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β−, n (52.0%)
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32Mg
|
3/2+#
|
|
| β− (36.0%)
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33Mg
|
| β−, 2n (12.0%)
|
31Mg
|
34
Na
|
11
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23
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7001340351700000000♠34.03517(96)#
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5.5(10) ms
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β−, 2n (50.0%)
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32Mg
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1+
|
|
| β− (35.0%)
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34Mg
|
| β−, n (15.0%)
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33Mg
|
35
Na
|
11
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24
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7001350424900000000♠35.04249(102)#
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1.5(5) ms
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β− (>99.9%)
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35Mg
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3/2+#
|
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| β−, n (<.1%)
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34Mg
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37
Na
|
11
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26
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37.05934(103)#
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1# ms [>1.5 µs]
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3/2+#
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Close
畫上#號的數據代表沒有經過實驗的証明，僅為理論推測。
Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. Standard atomic weights of the elements 2021 (IUPAC Technical Report). Pure and Applied Chemistry. 2022-05-04. ISSN 1365-3075. doi:10.1515/pac-2019-0603 （英語）.
- Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
- Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
- Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties （頁面存檔備份，存於網際網路檔案館）, Nuc. Phys. A 729, pp. 3-128 (2003).
- National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database （頁面存檔備份，存於網際網路檔案館） (retrieved Sept. 2005).
- David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.
