Sodium spectrum

The BO2 spectrum for a green flame might be suggested using boric acid as a colour producing agent, but it is too weak to use practically in firework compositions. 

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TABLE 11 YELLOW OR GOLD SODIUM SPECTRA GLITTER FORMULAS... 

The refractive index of CCI4 at 20°C and 589 nm, the D line of the sodium spectrum, is 1.4607. At this temperature the density of this compound is 1.59 g cm . Use this information to calculate a for CCI4. Criticize or defend the following proposition The prediction that = f(R/X) may have been premature. The consideration of Eq. (10.3) which led to this conclusion could just as well predict = f(a /X). 

The index of refraction is a measure of the ability of the alkane to bend (refract) light rays. The values reported are for light of the D line of the sodium spectrum ( D). 

D line spect The yellow line that is the first line of the major series of the sodium spectrum the doublet in the Fraunhofer lines whose almost equal components have wavelengths of 5895.93 and 5889.96 angstroms respectively. de, lTn ... 

Also important, besides the variables of the equation, are temperature of the solution, wavelength of the light source, and concentration of the solution. The standard light source used to measure optical rotation has been the bright yellow D lines of the sodium spectrum, but the single mercury line, X = 5461 A, is now used frequently for precision measurements. Generally, the specific rotation is reported at 20 °C and expressed as ... 

A rotation depends on the wavelength of light used and also on the temperature, so these data are given together with the rotation. In Solved Problem 5-4, the 25 means that the measurement was made at 25 °C, and the D means that the light used was the D line of the sodium spectrum. 

For example, if one of the carbons is first dipped into a sodium solution, thus picking up some sodium, the resulting spectrum when the arc is struck will be that of carbon plus sodium. The sodium light stands out because the sodium spectrum is very strong in the yellow region while the light from carbon is relatively continuous, spreading out clear across the spectrum. 

The absorption and emission spectra of metals such as copper, lithium, caesium, calcium and potassium involve lines at different wavelengths to those observed in the sodium spectrum. As with sodium, a few lines in each spectrum dominate the colours of compounds of these metals in the gas flame. This is the basis of the flame tests which are used to indicate the presence of compounds of these metals (see page 195). 

With the more complex spectra of heavier elements the different series have considerable overlap, as shown in figure 2-9. The upper spectrum is that of atomic sodium. Below it are shown the principal, sharp, diffuse, and fundamental series sorted out of the complete sodium spectrum. The doublet character of the separate series also is shown. The typical characteristic of each series to converge to a series limit also is clear. 

All chemists are familiar with the yellow color imparted to a flame by sodium atoms. The strongest yellow line (the D line) in the sodium spectrum is actually two closely spaced lines. The sodium D line arises from a transition from the excited configuration ls 2s 2p 3p to the ground state. The doublet nature of this and other lines in the Na spectrum indicates a doubling of the expected number of states available to the valence electron. 

It had become clearer that the Hght from a glowing soHd body shows a conHnuous spectrum while a metal that is vaporized emits a characterisHc line spectrum. The yeUow doublet in the sodium spectrum was an example. Charles Wheatstone, well known from the science of electricity, in 1835 invesHgated electrical arcs generated between metal electrodes. The metals he used were mercury, zinc, cadmium, Hn, bismuth and lead. He used a prism for studying the radiaHon from the arcs and observed the disHnct Hnes that consHtuted the spectrum. Further he noted that each metal had its special group of Hnes, which could possibly be used for element idenH-ficaHon. 

The value of the specific rotation depends on the temperature, which is fixed for reference purposes at 20° C. It also depends on the nature of the light source employed. The bright yellow D lines of the sodium spectrum or the yellow-green mercury line, 5461A, are the usual illuminants. The light used is indicated by affixing D or Hg to the symbol denoting the specific rotation. ... 

High-pressure sodium vapor lamps are used in street lighting. The two brightest lines in the sodium spectrum are at 589.00 and 589.59 run. What is the difference in energy per photon of the radiations corresponding to these two lines ... 

All the cations of Group I produce a characteristic colour in a flame (lithium, red sodium, yellow potassium, violet rubidium, dark red caesium, blue). The test may be applied quantitatively by atomising an aqueous solution containing Group I cations into a flame and determining the intensities of emission over the visible spectrum with a spectrophotometer Jlame photometry). 

Sodium is present in fair abundance in the sun and stars. The D lines of sodium are among the most prominent in the solar spectrum. Sodium is the fourth most abundant element on earth, comprising about 2.6% of the earth s crust it is the most abundant of the alkali group of metals. 

The thiazolium is not acidic enough for observing directly solvation of the molecule (or an hydrolysis and subsequent cleavage of the ring) (24) without adding a base, as it is the case for benzoxazolium or benzothiazolium. With the same dilution (10 mole liter ), it is necessary to add sodium ethylate to the solution of 2-methyl-4.5-diphenylthiazolium to observe the equilibrium described above. A new band appears in the UV spectrum at 320 nm that is attributed to the ethoxy derivative by analogy to what has been observed with other benzothiazoliums (26),... 

IR spectra can be recorded on a sample regardless of its physical state—solid liquid gas or dissolved m some solvent The spectrum m Eigure 13 31 was taken on the neat sample meaning the pure liquid A drop or two of hexane was placed between two sodium chloride disks through which the IR beam is passed Solids may be dis solved m a suitable solvent such as carbon tetrachloride or chloroform More commonly though a solid sample is mixed with potassium bromide and the mixture pressed into a thin wafer which is placed m the path of the IR beam... 

A compound is a cyclic ether of molecular formula C9H10O Its NMR spectrum is shown in Figure 16 10 Oxidation of the compound with sodium dichromate and sulfunc acid gave 1 2 benzenedicarboxylic acid What is the compound d... 

When levuhnic acid (CH3CCH2CH2CO2H) was hydrogenated at high pressure over a nickel catalyst at 220°C a single product C5Hg02 was isolated in 94% yield This compound lacks hydroxyl absorption in its IR spectrum and does not immediately liberate carbon dioxide on being shaken with sodium bicarbonate What is a reasonable structure for the compound" ... 

In 1817, Josef Fraunhofer (1787-1826) studied the spectrum of solar radiation, observing a continuous spectrum with numerous dark lines. Fraunhofer labeled the most prominent of the dark lines with letters. In 1859, Gustav Kirchhoff (1824-1887) showed that the D line in the solar spectrum was due to the absorption of solar radiation by sodium atoms. The wavelength of the sodium D line is 589 nm. What are the frequency and the wavenumber for this line ... 

In Figure 8.26 is shown the AXumLum Auger spectrum of sodium in crystalline NaCl. Once again, the formation of the >2 weakly, the core states can be observed. Also shown are peaks resulting from additional processes in which the initial photoelectron with... 

Figure 8.26 The ( 2 q) Auger spectrum of sodium in solid NaCl.

HC5N (cyanodiacetylene) interstellar, 120 rotational spectrum, 110 Na2S203 (sodium thiosulphate)... 

The ESR spectrum of the pyridazine radical anion, generated by the action of sodium or potassium, has been reported, and oxidation of 6-hydroxypyridazin-3(2//)-one with cerium(IV) sulfate in sulfuric acid results in an intense ESR spectrum (79TL2821). The self-diffusion coefficient and activation energy, the half-wave potential (-2.16 eV) magnetic susceptibility and room temperature fluorescence in-solution (Amax = 23 800cm life time 2.6 X 10 s) are reported. 

Sodium p-toluenesulfinate [824-79-3] M 178.2, pK 2.80 (1.99)(for -S02 ). Crystd from water (to constant UV spectrum), and dried under vacuum or extracted with hot benzene, then dissolved in EtOH-H20 and heated with decolorising charcoal. The solution was filtered and cooled to give crystals of the dihydrate. 

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