Because it is an electropositive metal, magnesium can be act as a 'sacrificial' electrode to protect iron and steel structures because it corrodes away preferentially when they are exposed to water which otherwise would cause rusting. So better bikes, better bombs and better bums. Thank you very much to science writer John Emsley for telling the tale of Magnesium. Next week the illuminating story of the element that spawned a light bulb but really needs to work on its image.
If any element needs a change of PR this is the one. It's brittle, prone to ponginess and arguably the dunce of the periodic table. Even the man who discovered osmium treated it rather sniffily. It reeked - or at least some of its compounds did. Tennant described the "pungent and penetrating smell" as one of the new element's "most distinguishing characters". So he called it osmium - osme being the Greek for odour.
That's Quentin Cooper who will be undressing osmium for us in next week's Chemistry in its element, I hope you can join us. I'm Chris Smith, thank you for listening, see you next time. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.
Click here to view videos about Magnesium. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists.
Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium.
G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership. Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by. Origin of the name. The name is derived from Magnesia, a district of Eastern Thessaly in Greece.
Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database. Electronegativity Pauling scale. Common oxidation states. Atomic mass. Magnesium Metal is also available in ultra high purity and as nanoparticles.
For thin film applications it is available as rod, pellets, pieces, granules and sputtering targets and as either an ingot or powder. Magnesium Oxide 25 isotopic material is generally immediately available. Typical and custom packaging is available. Additional technical, research and safety MSDS information is available as is a Reference Calculator for converting relevant units of measurement.
Magnesium Metal Isotope. Lithium Magnesium Sputtering Target. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized gallon liquid totes, and 36, lb.
Related Elements Magnesium 12 Mg Fallon said that many calculations suggest that Mg nuclei are very deformed, and possibly football-shaped, so the two added neutrons in Mg may be buzzing around the core to form a so-called halo nucleus rather than being incorporated into the shape exhibited by neighboring magnesium isotopes.
Crawford said that additional measurements and theory work on Mg, and that nearby isotopes could help to positively identify the shape of the Mg nucleus, and to explain what is causing the change in nuclear structure. Note: Content may be edited for style and length. Science News. Journal Reference : H. Crawford, P. Fallon, A. Macchiavelli, P. Doornenbal, N. Aoi, F. Browne, C. Campbell, S. Chen, R.
Clark, M. Cromaz, E. It is consistent with the upper envelope of the data. The metallicity is lowered as the number of high-mass, metal-producing stars is reduced.
As one can see, all of the models are consistent with the data at high redshift. The evolution of the metallicity as in Fig. The black curve is taken directly from Fig.
As iron is often used as a tracer for chemical evolution, we show in Fig. The effect of the rotation velocity is here negligible as it affects very little the mass of the exploding iron core. The data are again taken from Rafelski et al. As in Fig. The solid black and red lines correspond to the two sets of yields from Nomoto et al. The solid lines are derived using the single-sloped IMF Model 1. As one can see, the evolution of carbon is hardly affected by the choice of different yields.
While there is some dependence on the choice of yields in the nitrogen and oxygen abundances, the difference in the calculated abundance is small compared to the dispersion in the data that are taken from multiple Galactic sources listed in the caption of each figure. The total magnesium abundance displayed in Fig. The black lines are derived from the metallicity-dependent yields of Nomoto et al.
The observational constraints come from Cayrel et al. Observations come from Yong et al. These results are shown by the corresponding dashed curves. As one can see, the abundances of carbon, oxygen, and magnesium are virtually unaffected by the IM mode. This is well within the observational dispersion. Note that the magnesium abundance shown in Fig. As we will see in the next subsection, the abundances of the individual magnesium isotopes are sensitive to the inclusion of the IM mode.
In order to study the production of the magnesium isotopes in the ISM, we use the yields discussed in Sections 2. Solar abundances are taken from Asplund et al. We now compare the results of our model to the observed Mg isotope abundance measurements, focusing on the comparison between different stellar evolution models and different sets of yields.
In contrast, the green curves employ the Karakas yields for IM stars [with Nomoto et al. Here we see an enhancement in 26 Mg. Not surprisingly, there is further enhancement of 26 Mg in this case when the additional IM mode Model 2a is included.
Overall, the ratio of the two heavier isotopes is relatively fixed and does not depend sensitively on the addition of an IM mode. The green curves show the ratio using the yields from Karakas for IM stars. Data are taken from Yong et al. In contrast, we see in Figs 9 — 11 very significant differences between the models for the ratios of 26 Mg to the total Mg abundance Fig.
Once again, solid lines [black lines corresponding to the yields of Nomoto et al. Had we used the Karakas yields [with Nomoto et al. That is, the ratios to total Mg are not particularly sensitive to the choice of IM yields. Using the Nomoto et al. This is because, as noted earlier, we are showing cosmic averages of the element abundances in the ISM.
In an inhomogeneous model such as that described in Dvorkin et al. Here we are considering only the evolution in Model 1 no IM mode and the yields of Nomoto et al. The black curve is reproduced from Fig. Similarly, Figs 13 — 15 show the impact of the lower mass limit, m inf , of the IM mode.
In these figures, we are comparing Models 2a and 2b, so all results include the addition of the IM mode albeit with different lower mass limits. Solid curves correspond to Model 2a and are identical to the dashed curves in Figs 9 — Dashed curves here correspond to Model 2b, which increases the heavy isotope ratios.
This leads to further improvement of the model predictions using the Nomoto et al. Finally, it is interesting to analyse the impact of rotation in massive stars on the evolution of the Mg isotope ratios. The red solid curve here is the same as that given in Fig. As one can see, while rotation lowers the Mg abundance, the effect on the total Mg abundance is rather small. As we already saw in Fig. The evolution of the total magnesium abundance in the ISM as a function of the iron abundance.
In contrast, rotation has a large effect on the isotopic ratios of Mg. When the rotational velocity is relatively low, the predicted ratios are in relatively good agreement with observations. At higher rotational velocities, the yields of the heavy isotopes are strongly dependent on the stellar mass. Limongi, private communication. Because of the power-law dependence of the IMF, the lower mass end of the IMF for massive stars dominates the chemical evolution and when integrated over the IMF leads to a large enhancement of 26 Mg.
This is clearly seen in Fig. Our knowledge of the detailed history of star formation both in the Galaxy and on a cosmic scale relies on stellar nucleosynthesis and our ability to trace the evolution of the chemical abundances from the formation of the first stars at zero metallicity to the present day at solar metallicity. Different elements and isotopes reveal different aspects of the stellar history.
Other elements, such as iron, span a combination of origins including both Type I and II supernovae. The relative importance of intermediate-mass stars can be gleaned from the abundances of elements such as nitrogen and as we have argued here, the heavy isotopes of Mg. Here, we have worked in the context of a model of cosmic chemical evolution. The model is constrained by the observed star formation rate density obtained from the luminosity function measured at high redshift.
The optical depth to reionization derived from CMB observations also constrains the rate of star formation at high redshift. While such models necessarily carry large uncertainties due to the choice of the IMF, as well as uncertainties in the calculated stellar yields , general evolutionary tendencies can be extracted from them.
Recall that the type of evolutionary model we have employed calculates only average abundances, and a more detailed model such as that based on merger trees is needed to understand the degree of dispersion observed in the data Dvorkin et al.
In this paper we have explored the evolution of the magnesium isotopic abundances in the ISM using our model of cosmic chemical evolution based on hierarchical structure formation.
The abundances of the heavier Mg isotopes are primarily produced in IM stars and therefore the abundance ratios of these isotopes provide insight into the relative importance of IM stars in chemical evolution.
It is interesting to note that the apparent conflict between the EBL density and IR measurements may also imply a need for an additional component of IM stars Fardal et al. Taking into account the inherent uncertainty introduced by the choice of stellar yields, we have explored several sets of nucleosynthetic yields. As expected, we confirm that the bulk of 24 Mg in the ISM is produced by massive stars. However, a single-sloped Salpeter-like IMF does not reproduce the observed evolutionary behaviour of 25 Mg and 26 Mg, which show enhancements at later metallicities.
Instead, an additional component making the IMF bimodal of IM stars seems to be required to fit the observational constraints on the isotopic ratios. This conclusion holds independently of the choice of yields. However, the relative importance of the IM component is very sensitive to the choice of yields from IM stars.
Adding to the uncertainty in the heavy isotopic yields is the degree of rotational velocity, which can strongly affect the yield of 26 Mg. It is clear that there is a strong interplay between observations of element and isotopic abundances, calculations of nucleosynthetic yields, and the modelling of the chemical history of these abundances.
Progress in any one of these three areas relies on progress in the other two.
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