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The rubidium content in minerals is often calculated and quoted in terms of Rb 2 O. In reality, the rubidium is typically present as a component of (actually, an impurity in) silicate or aluminosilicate. A major source of rubidium is lepidolite, KLi 2 Al(Al,Si) 3 O 10 (F,OH) 2, wherein Rb sometimes replaces K. Rb 2 O is a yellow colored solid.
Rubidium sesquioxide is a chemical compound with the formula Rb 2 O 3 or more accurately Rb 4 O 6.In terms of oxidation states, Rubidium in this compound has a nominal charge of +1, and the oxygen is a mixed peroxide (O 2− 2) and superoxide (O − 2) for a structural formula of (Rb +) 4 (O − 2) 2 (O 2− 2). [4]
Rubidium is a chemical element; it has symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. [9] Rubidium is the first alkali metal in the group to have a density higher than water.
The standard enthalpy of formation of the crystalline rubidium oxalate is 1325.0 ± 8.1 kJ/mol. [9] The decomposition of rubidium oxalate with the release of carbon monoxide and subsequently carbon dioxide and oxygen takes place at 507–527 °C (945–981 °F; 780–800 K). [6] [2] Rb 2 C 2 O 4 → Rb 2 CO 3 + CO↑ Rb 2 CO 3 → Rb 2 O + CO 2 ...
The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: . 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g). Metals in the middle of the reactivity series, such as iron, will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt, such as iron(II) sulfate:
Similar to potassium permanganate, the two-step decomposition of rubidium permanganate leads to the formation of rubidium manganate intermediates. It breaks down into manganese dioxide, rubidium oxide and oxygen. [4] The decomposition temperature is between 200 and 300 °C. [7] Drift-away oxygen caused an 8% mass loss in the product. [7]
It can be created by slowly exposing elemental rubidium to oxygen gas: [3] Rb(s) + O 2 (g) → RbO 2 (s) Like other alkali metal hyperoxides, crystals can also be grown in liquid ammonia. [4] Between 280 and 360 °C, Rubidium superoxide will decompose, leaving not rubidium sesquioxide (Rb 2 O 3), but rather rubidium peroxide (Rb 2 O 2). [3]
This causes lithium to form the oxide exclusively on reaction with oxygen at room temperature. This effect becomes drastically weaker for the larger sodium and potassium, allowing them to form the less stable peroxides. Rubidium and caesium, at the bottom of the group, are so large that even the least stable superoxides can form.