Rubidium hydrogen sulfate, sometimes referred to as rubidium bisulfate, is the half neutralized
rubidium salt
In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...
of
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...
. It has the formula RbHSO
4.
Synthesis
It may be synthesised with water and a stoichiometric amount of
rubidium disulfate. Reaction takes place where there is no humidity:
[S. B. Rasmussen, H. Hamma, K. M. Eriksen, G. Hatem, M. Gaune-Escard, R. Fehrmann: "Physico-chemical properties and transition metal complex formation in alkali pyrosulfate and hydrogen sulfate melts". VII International Conference on Molten Slags Fluxes and Salts, The South African Institute of Mining and Metallurgy, 2004]
Volltext
(PDF; 661 kB)
:
There is another method of creation. It is similar to the synthesis of
sodium sulfate
Sodium sulfate (also known as sodium sulphate or sulfate of soda) is the inorganic compound with formula Na2SO4 as well as several related hydrates. All forms are white solids that are highly soluble in water. With an annual production of 6 mill ...
and
potassium sulfate. This reaction requires
rubidium chloride
Rubidium chloride is the chemical compound with the formula RbCl. This alkali metal halide salt is composed of rubidium and chlorine, and finds diverse uses ranging from electrochemistry to molecular biology.
Structure
In its gas phase, RbCl is d ...
and a little bit of warm sulfuric acid. Some
hydrogen chloride
The Chemical compound, compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colorless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hyd ...
is also produced during the reaction.
:
Properties
It is a
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption (chemistry), absorption or adsorption from the surrounding Natural environment, environment, which is usually at normal or room temperature. If water mol ...
compound. It has a
monoclinic
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three Vector (geometric), vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in t ...
crystal structure, its structure is P2
1/n. Dimensions of the unit cell are: a = 1440 pm, b = 462.2 pm, c = 1436 pm and β = 118.0°. Its crystals are
isomorphs with
ammonium hydrogen sulfate crystals.
[J. P. Ashmore, H. E. Petch: "The Structure of RbHSO4 in its Paraelectric Phase" in ''Can. J. Phys'' 1975, ''53''(24), S. 2694-2702. ]
Its
standard enthalpy is −1166 kJ/mol.
[L. A. Cowan, R. M. Morcos, N. Hatada, A. Navrotsky, S. M. Haile: "High temperature properties of Rb3H(SO4)2 at ambient pressure: Absence of a polymorphic, superprotonic transition" in ''Solid State Ionics'' 2008, ''179'', S. 305-313]
Volltext
(PDF; 837 kB) During its dissolution in water, there is 15.62 kJ/mol energy produced.
[M. de Forcrand: "Sur les chlorures et sulfates de rubidium et de caesium" in ''Compt. Rend. Hebd.'' 1906, ''143'', S. 98]
Volltext
/ref>
After warming up it decomposes to rubidium disulfate and water:[R. Abegg, F. Auerbach: "Handbuch der anorganischen Chemie". Verlag S. Hirzel, Bd. 2, 1908. S. 43]
Volltext
/ref>
:
Like potassium
Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...
and caesium
Caesium (IUPAC spelling; also spelled cesium in American English) is a chemical element; it has Symbol (chemistry), symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of , which makes it one of only f ...
, rubidium has another hydrogen sulfate compound as well: Rb3H(SO4)2.
References
{{rubidium compounds
Rubidium compounds