Question

Compare the isotopes of magnesium on the basis of nuclei composition

Answer 1

Answer:

Explanation:

Isotopes of magnesium

Main isotopes of magnesium (12Mg)

Iso­tope Decay

abun­dance half-life (t1/2) mode pro­duct

24Mg 79.0% stable

25Mg 10.0% stable

26Mg 11.0% stable

Standard atomic weight Ar, standard(Mg)  

[24.304, 24.307][1]

Conventional: 24.305

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Magnesium (12Mg) naturally occurs in three stable isotopes, 24Mg, 25Mg, and 26Mg. There are 18 radioisotopes that have been discovered, ranging from 19Mg to 40Mg. The longest-lived radioisotope is 28Mg with a half-life of 20.915 hours. The lighter isotopes mostly decay to isotopes of sodium while the heavier isotopes decay to isotopes of aluminium. The shortest-lived is 19Mg with a half-life of 5 picoseconds.

The abundances of the naturally occurring isotopes of magnesium.

List of isotopes

Nuclide[2]

Z N Isotopic mass (Da)[3]

[n 1] Half-life

[n 2] Decay

mode

[n 3] Daughter

isotope

[n 4] Spin and

parity

[n 5][n 2] Natural abundance (mole fraction)

Normal proportion Range of variation

19Mg 12 7 19.03417(5) 5(3) ps 2p 17Ne 1/2−#  

20Mg 12 8 20.0187631(2) 93(5) ms β+ (69.7%) 20Na 0+  

β+, p (30.3%) 19Ne

21Mg 12 9 21.0117058(8) 118.6(5) ms β+ (66.9%) 21Na 5/2+  

β+, p (32.6%) 20Ne

β+, α (0.5%) 17F

22Mg 12 10 21.9995707(3) 3.8755(12) s β+ 22Na 0+  

23Mg 12 11 22.99412394(17) 11.317(11) s β+ 23Na 3/2+  

24Mg 12 12 23.985041697(14) Stable 0+ 0.7899(4) 0.78958–0.79017

25Mg 12 13 24.98583696(5) Stable 5/2+ 0.1000(1) 0.09996–0.10012

26Mg[n 6] 12 14 25.98259297(3) Stable 0+ 0.1101(3) 0.10987–0.11030

27Mg 12 15 26.98434063(5) 9.435(27) min β− 27Al 1/2+  

28Mg 12 16 27.9838766(21) 20.915(9) h β− 28Al 0+  

29Mg 12 17 28.988617(12) 1.30(12) s β− 29Al 3/2+  

30Mg 12 18 29.990463(4) 313(4) ms β− (99.94%) 30Al 0+  

β−, n (0.06%) 29Al

31Mg 12 19 30.996648(3) 236(20) ms β− (93.8%) 31Al 1/2(+)  

β−, n (6.2%) 30Al

32Mg 12 20 31.999110(4) 86(5) ms β− (94.5%) 32Al 0+  

β−, n (5.5%) 31Al

33Mg 12 21 33.005327(3) 90.5(16) ms β− (86%) 33Al 3/2−  

β−, n (14%) 32Al

34Mg 12 22 34.00894(3) 20(10) ms β− (70%) 34Al 0+  

β−, n (30%) 33Al

35Mg 12 23 35.01679(29) 70(40) ms β−, n (52%) 34Al 7/2−#  

β− (48%) 35Al

36Mg 12 24 36.02188(74) 3.9(13) ms β− 36Al 0+  

37Mg 12 25 37.03029(75) 8(4) ms β− 37Al (3/2−)  

β−, n 36Al

38Mg 12 26 38.03658(54)# 1# ms [>260 ns]   0+  

40Mg 12 28 40.05191(54)# 1# ms β−, n 39Al 0+  

β− 40Al

( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.

# – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).

Modes of decay:

n: Neutron emission

p: Proton emission

Bold symbol as daughter – Daughter product is stable.

( ) spin value – Indicates spin with weak assignment arguments.

Used in radiodating events early in the Solar System's history

Isotopes of the chemical elements

Group 1 2 3   4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Period Alkali metals Alkaline earth metals              Pnicto­gens Chal­co­gens Halo­gens Noble gases