Lithium Li

Lithium forms structural alloys with both aluminum and magnesium. Mg-Li alloys have the highest strength-to-weight ratio of all structural materials. Li is used as a degasser to scavenge oxygen in the production of steel and of copper. It is also used as the anode (positive terminal) of some batteries. 

Almost as interesting is the role of lithium s lighter stable isotope, 6Li, in the production of the hydrogen bomb. The crucial tritium is produced by bombarding 6Li with neutrons 6Li + n - 3H (tritium) + 4He. The radioactive tritium (3H) is a major fusion fuel when reacting with deuterium (2H) in the thermonuclear bomb. Because Li effectively absorbs neutrons it is also useful for neutron-shielding devices. 

Natural isotopes of lithium and their solar abundances 

From the isotopic decomposition ofnormal lithium onefinds thatthemass-6 isotope, 6Li, is the lesser abundant of lithium s two isotopes 7.5% of terrestrial Li. Lithium presents some of the most interesting abundance questions in astrophysics (see also 7Li). Using the total abundance of elemental Li = 57.1 per million silicon atoms in solar-system matter, this isotope has 

Lithium is not an abundant element, only 29th in rank of all element abundances, so that 6Li is one of the least abundant nuclear species lighter than iron. Only 9Be is less abundant than 6Li and the comparably rare 10B among the light nuclei. These are such low-abundance isotopes that their processes of nucleosynthesis must be rare or very inefficient. 

Most battery systems in which lithium is apphed as anode material belong to the group using nonaqueous electrolytes, but there is one system that works with water serving as solvent and reactant as weU. This is only possible because hthium forms a passive layer in solutions containing higher amounts of caustic [104-107]. 

Nevertheless, the water is decomposed with evolution of hydrogen but under controlled conditions and with a reasonable reaction rate. With water as the active cathode material, the battery system-used in military underwater applications - can be designed as (—) Li/KOH/H20 (-I-) [108]. 

The electrochemical equivalent of 3860 Ah kg is the highest of all metal anodes and the OCV of 2.7-2.8 V (depending on electrolyte concentration) is also rather high. 

The most sensitive analytical line for lithium is at 670.785 nm with a characteristic concentration of Co = 0.006 mg/L in an air/acetylene flame, and a linear working range up to about Ara x = 3 mg/L. The characteristic mass at this line, using a transversely heated graphite tube atomizer, is mo = 1 pg. The lithium line at 670.785 nm is actually a doublet with a separation of about 15 pm, and it also exhibits an isotope shift of the same magnitude [150]. However line broadening in conventional atomizers is usually too pronounced, so that the individual fine structure components cannot be resolved. 

Lithium has one less sensitive analytical line that may be used for the determination of higher analyte concentrations. Both absorption lines are compiled in Table 6.14, together with information about their spectral environment. 

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The small lithium Li" and beryllium Be ions have high charge-radius ratios and consequently exert particularly strong attractions on other ions and on polar molecules. These attractions result in both high lattice and hydration energies and it is these high energies which account for many of the abnormal properties of the ionic compounds of lithium and beryllium. 

The Elements Lithium (Li), Sodium (Na), and Potassium (K) all formed oxides in the ratio of two atoms per oxygen atom R2O... 

The horizontal rows in the table are referred to as periods. The first period consists of the two elements hydrogen (H) and helium (He). The second period starts with lithium (Li) and ends with neon (Ne). 

Lithium (Li), an alkali metal, has properties similar to and has a diagonal relationship with —... 

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