Sodium line spectrum

The first result is interesting inasmuch as it is thus possible to displace the centers of ellipses not only horizontally as usual relative to the fixed sodium lines in the spectrum, but also vertically relatively to... 

N. E. Erickson Regarding iron for calibration, some workers run in a time mode but use a sinusoidal drive. This results in an extremely nonlinear velocity scale, and a two-line pattern, such as in sodium nitro-prusside, is just not reasonable for a standard. One needs more lines, with a wider separation. I would like a standard which gives six lines, and hence I favor iron. Perhaps the Bureau of Standards, and I know I have spoken with you (Spijkerman) about this and you argue against it, could calibrate iron foils, which would provide a known six line spectrum. 

They noticed that when ordinary salt was sprinkled into the flame of a Bunsen burner, a yellow line was seen through the spectroscope in exactly the position formerly occupied by the dark double line of the sun s spectrum known as the D-line. Attempting then to observe the dark D-line and the bright sodium line simultaneously, by allowing... 

FIGURE 5.6 (a) The visible line spectrum of energetically excited sodium atoms consists of a closely spaced pair of yellow lines, (b) The visible line spectrum of excited hydrogen atoms consists of four lines, from indigo at 410 nm to red at 656 nm. 

Sodium naphthalenide behaves similarly when the solvent is changed from tetrahydrofuran to 1,2-dimethoxyethane. The formation of solvent-separated from contact ion pairs is shown by a dramatic simplification of the ESR spectrum the 100-line spectrum of the contact ion pair, due to the spin-spin coupling of the unpaired electron with the four equal hydrogen nuclei in the a- and y9-positions, together with the sodium nucleus (/ = 3/2), collapses to a 25-line spectrum as the interaction with the sodium ion is disrupted [169, 170]. 

The refractive index of a substance is a dimensionless constant that normally decreases with increasing temperature values are taken at 20°C or 25°C using the mean value taken for the two sodium lines of the spectrum. The optical systems that are used to exploit the refractive index for detection purposes are many and varied. One procedure is to construct a cell in the form of a hollow prism through which the mobile phase can flow. A ray of light is passed through the prism, which will be deviated from its original path, and is then focused onto a photocell. As the refractive... 

Problem 5.11 Interpret the diagram below regarding the D lines of the sodium emission spectrum. 

One of the earliest and most famous examples of the use of spectrometry to study the solar system occurred in 1868. While observing a solar eclipse in India, the French astronomer Pierre Janssen (1824-1907) found a new spectral line in sunlight very close to one found in the spectrum of sodium. Janssen was able to show, however, that the new yellow light was different from the sodium line. Indeed, it was a spectral line that had never before been observed on Earth. Janssen hypothesized that the presence of the line could be explained only if the Sun s atmosphere contained an element that had not yet been discovered on Earth. The British astronomer Sir Norman Lockyer (1836-1920) later suggested the name helium for the element, a name based on the Greek word for "sun," helios. It was almost 30 years later that Janssen s bold hypothesis was confirmed. In 1895, the British chemist and physicist Sir William Ramsay (1852-1916) first detected helium on Earth, during a series of experiments on an ore of uranium called clevite. 

Each element has a characteristic line spectrum that can be used to identify the element. Note that line emission spectra can also be obtained by heating a salt of a metal with a flame. For instance, common salt (sodium chloride) provides a strong yellow light to the flame coming from excited sodium, while copper salts emit a blue-green light and lithium salts a red light. The colors of fireworks are due to this phenomenon. 

FIGURE 6 21 Energy-level diagrams for (a) a sodium alom showing the source of a line spectrum and (b) a simple molecule showing the source of a band spectrum. 

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