Rubidium oxide

Rubidium hydroxide, 27 821-822 Rubidium iodide, 27 823 Rubidium metal alloys, 27 816 Rubidium metal, pure, 27 818 Rubidium oxides, 27 816, 823 Rubidium ozonide, 78 417 Rubidium silicates, 22 452 Rubidium sulfate, 27 821 Rubidium superoxide, 78 417 Rubidium tetrahydroborate physical properties of, 4 194t Ruby, 2 405 color, 7 329 Ruby glass, 7 344... 

Rubidium [7440-17-7/, Rb, is an alkali metal, ie, in Group 1 (IA) of the Periodic Table. Its chemical and physical properties generally He between those of potassium (qv) and cesium (see Cesium and cesium compounds Potassium compounds). Rubidium is the sixteenth most prevalent element in the earth s cmst (1). Despite its abundance, it is usually widely dispersed and not found as a principal constituent in any mineral. Rather it is usually associated with cesium. Most rubidium is obtained from lepidolite [1317-64-2], an ore containing 2—4% rubidium oxide [18088-11-4]. Lepidolite is found in Zimbabwe and at Bemic Lake, Canada. 

High Temperature Measurements of the Rates of Uptake of Molybdenum Oxide, Tellurium Oxide, and Rubidium Oxide Vapors by Selected Oxide Substrates... 

The rates of uptake of molybdenum, tellurium, and rubidium oxide vapors by substrates of calcium ferrite and a clay loam have been measured in air over a temperature range of 900° to 1500°C. and a partial pressure range of about 10r7 to 10 atm. The measured rates of uptake of molybdenum and tellurium oxide vapors by molten calcium ferrite and of rubidium oxide vapor by both molten clay loam and calcium ferrite were controlled by the rates of diffusion of the oxide vapors through the air. The measured rates of uptake of molybdenum and tellurium oxide vapors by molten clay loam were controlled by a combination of a slow surface reaction and slow diffusion of the condensate into the substrate. 

Figures 6 and 7 show the uptake of rubidium oxide vapor by various sized particles of clay loam and calcium ferrite at 1400°C. There is uncertainty as to the molecular species found in rubidium oxide vapor under the experimental conditions. Data furnished by Bedford and Jackson indicate that the vapor should consist of a mixture of RbO and Rb molecules with RbO predominating (4). Experimental work by Norman and Staley indicate that the vapor should consist predominately of Rb with minor amounts of Rt O molecules (13). To calculate vapor pressures it was assumed that the vapor consisted only of RbO. Since the molecular weight of Rb is only 16% less than that of RbO, no large error is introduced by this assumption even if the vapor consists of Rb molecules.

Figures 8, 10, and 12 show the initial rates (at t = 0) of uptake of the molybdenum, tellurium, and rubidium oxide vapors by samples of...

For the uptake of molybdenum oxide vapor by the clay loam particles, the uptake of rubidium oxide vapor by the calcium ferrite, and the uptake of the tellurium oxide by both the clay loam and the calcium ferrite, the uptake vs. time plots are curved, and it is not immediately obvious what the rate-determining steps are. Plots of amounts of uptake at constant time and initial rates of uptake vs. particle diameters and diameters squared were therefore made. 

These plots show that for the uptake of both tellurium and rubidium oxide vapors by the calcium ferrite particles the rate-determining step is also the diffusion of the oxide vapor molecules through the air. The curvature of the plots showing amounts of uptake vs. time is caused by... 

Rubidium ignites spontaneously when exposed to oxygen to form rubidium oxide, RbaO. Rubidium exists as two isotopes fRb (84.91 u) and (jyRb (86.91 u). If the average atomic mass of rubidium is 85.47 u, determine the percentage abundance of Rb. 

Answer (a) Since rubidium is an alkali metal, we would expect Rb20 to be a basic oxide. This is indeed true, as shown by rubidium oxide s reaction with water to form rubidium hydroxide ... 

Pr7012 7-PRASEODYMIUM 12-OXIDE 1328 Rb20 RUBIDIUM OXIDE 1374... 

Phosphoric acid H3OP 42.4 13.4 Rubidium oxide ORbj 505 20... 

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