Caesium periodate

Caesium periodate, CsI04.—The periodate is prepared by the action of caesium carbonate on periodic acid.8 It forms orthorhombic plates, not isomorphous with the corresponding salts of rubidium and potassium.8 It has a density of 4 259 at 15° C., and its solubility at 15° C. is 2 15 grams in 100 grams of water. 

In the lithium and sodium Periods, no intervening subshells are filled between Groups II and III in the potassium and rubidium Periods, however, the 3d and 4d subshells must be filled between these Groups, and in the caesium Period, both the 4f and 5d subshells are filled. 

The alkali metals form a homogeneous group of extremely reactive elements which illustrate well the similarities and trends to be expected from the periodic classification, as discussed in Chapter 2. Their physical and chemical properties are readily interpreted in terms of their simple electronic configuration, ns, and for this reason they have been extensively studied by the full range of experimental and theoretical techniques. Compounds of sodium and potassium have been known from ancient times and both elements are essential for animal life. They are also major items of trade, commerce and chemical industry. Lithium was first recognized as a separate element at the beginning of the nineteenth eentury but did not assume major industrial importance until about 40 y ago. Rubidium and caesium are of considerable academic interest but so far have few industrial applications. Francium, the elusive element 87, has only fleeting existence in nature due to its very short radioactive half-life, and this delayed its discovery until 1939. 

Robertson [ 57 ] has measured the adsorption of zinc, caesium, strontium, antimony, indium, iron, silver, copper, cobalt, rubidium, scandium, and uranium onto glass and polyethylene containers. Radioactive forms of these elements were added to samples of seawater, the samples were adjusted to the original pH of 8.0, and aliquots were poured into polyethylene bottles, Pyrex-glass bottles and polyethylene bottles contained 1 ml concentrated hydrochloric acid to bring the pH to about 1.5. Adsorption on the containers was observed for storage periods of up to 75 d with the use of a Nal(Tl) well crystal. Negligible adsorption on all containers was registered for zinc, caesium, strontium, and... 

A remarkable property of the atomic weights was discovered, in the sixties, independently by Lothar Meyer and Mendeleeff. They found that the elements could be arranged in rows in the order of their atomic weights so that similar elements would be found in the same columns. A modernised form of the Periodic Table will be found on pp. 106, 107. It will be noticed, for example, that the "alkali" metals, Lithium, Sodium, Rubidium and Caesium, which... 

For many elements, the atomization efficiency (the ratio of the number of atoms to the total number of analyte species, atoms, ions and molecules in the flame) is 1, but for others it is less than 1, even for the nitrous oxide-acetylene flame (for example, it is very low for the lanthanides). Even when atoms have been formed they may be lost by compound formation and ionization. The latter is a particular problem for elements on the left of the Periodic Table (e.g. Na Na + e the ion has a noble gas configuration, is difficult to excite and so is lost analytically). Ionization increases exponentially with increase in temperature, such that it must be considered a problem for the alkali, alkaline earth, and rare earth elements and also some others (e g. Al, Ga, In, Sc, Ti, Tl) in the nitrous oxide-acetylene flame. Thus, we observe some self-suppression of ionization at higher concentrations. For trace analysis, an ionization suppressor or buffer consisting of a large excess of an easily ionizable element (e g. caesium or potassium) is added. The excess caesium ionizes in the flame, suppressing ionization (e g. of sodium) by a simple, mass action effect ... 

V. 1 Olivier a trace of iodine. L. Dieulafait found traces of lithium, rubidium, and caesium salt H. Beckurts, chlorates and perchlorates up to 5 64 per cent. M. Marcker, borates and humus C. F. Schfinbein, nitrites and ammonia R. Wagner, iodine and bromine. H. Griineberg says the former is present as iodate or periodate. 

Caesium is a metal in Group I of the Periodic Table, a State two physical properties of caesium. [2]... 

After Bunsen had detected and isolated caesium, spectroscopy was taken up with great enthusiasm by William Crookes, and this led to his detection and isolation of thallium in 1861.191 Crookes letters to Charles Hanson Greville Williams, who was also working with the spectroscope, and who felt he deserved some of the credit for the discovery of thallium, have been published.192 The use of spectrochemistry in the search for hitherto unknown chemical elements in Britain over the period 1860-1869 has been described. It was perceived that, like Crookes, a scientist could make his reputation by discovering a new element. This resulted in several claims for the existence of new elements that later proved to be unfounded.193 Once Kirchhoff had established beyond doubt that the dark Fraunhofer lines were caused by the same element that caused emission lines of identical wavelengths, the way was open for the chemical analysis of the atmosphere of the sun and stars. This was a process which had been declared to be an impossibility by Auguste Comte less than 30 years previously.194... 

Dissolve tetraethylene glycol ditoluenesulfonate, 13 (6.05 g) and caesium toluenesulfonate (3.64 g) in dry degassed DMF (100 mL) and transfer it to the pressure-equalising dropping funnel attached to the reaction vessel. Add the solution over a period of 30 min to the reaction mixture, maintaining the reaction conditions as described in step 4. 

The inclusion of iron, cobalt, nickel, and certain other metals in Group VIII.4 enables the alkali-metals lithium, sodium, potassium, rubidium, and caesium to be placed in their natural position as a subgroup of Group I. of the periodic system, in juxtaposition to the related sub-group containing copper, silver, and gold (p. 3). This arrangement... 

Atomic Weight.—The chemical properties of caesium indicate its close relationship to the other alkali-metals. It is univalent, forming compounds of the type CsX, its atomic weight and hydrogen equivalent being the same. Its atomic weight is of the order Cs =133 a value conformed by the specific-heat method (Vol. I., p. 88) by the isomorphism of the caesium compounds with those of potassium, ammonium, and rubidium (Vol. I., p. 74) by the correspondence of the properties of the metal and its compounds with the periodic system by the formation of a univalent cation and by the depression of the freezing-point of bismuth chloride and mercuric chloride produced by caesium chloride. 

The three alkali-metals potassium, rubidium, and caesium form numbers 4, 6, and 8 of the even series of the most strongly electropositive group of the periodic classification, and have the atomic-sequence numbers 19, 37, and 55, differing at each step by 18 units, the atomic number of rubidium being thus exactly the mean of the atomic numbers of potassium and caesium. The increase by 18 units... 

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