Rubidium perchlorate

Crystal structure
__ Rb + __ Cl 7+ __ O 2−
Crystal system	orthorhombic
Space group	Pnma (No. 62)
Lattice parameters	a = 749.0 pm, b = 926.9 pm, c = 581.4 pm, Z = 4
General
Surname	Rubidium perchlorate
Ratio formula	RbClO 4
Brief description	white, odorless, hygroscopic crystals
External identifiers / databases
CAS number 13510-42-4 EC number 236-840-1 ECHA InfoCard 100.033.476 PubChem 23673707 Wikidata Q412328
properties
Molar mass	184.92 g · mol -1
Physical state	firmly
density	2.8 g cm −3
Melting point	192 ° C
solubility	poor in water (10.9 g l −1 at 21.3 ° C, 180 g l −1 at 100 ° C)
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 272-302-315-319-332-335 P: 220-261-305 + 351 + 338
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Rubidium perchlorate is the rubidium salt of perchloric acid .

Manufacturing

Rubidium perchlorate can be produced by carefully heating a rubidium chlorate solution, the rubidium chlorate then disproportionates to rubidium perchlorate and rubidium chloride . This releases oxygen .

${\displaystyle {\ce {2RbClO3 -> RbClO4 + RbCl + O2 ^}}}$

Rubidium perchlorate can also be obtained by chemical oxidation of rubidium chlorate by mixing aqueous rubidium chlorate solutions with strong oxidizing agents such as e.g. B. converts potassium permanganate and suitable catalysts . The easiest way is to react or neutralize a rubidium carbonate or rubidium hydroxide solution with perchloric acid :

${\displaystyle {\ce {Rb2CO3 + 2HClO4 -> 2RbClO4 v + CO2 ^}}}$

${\displaystyle {\ce {RbOH + HClO4 -> RbClO4 v + H2O}}}$

properties

Physical Properties

The solubility of rubidium perchlorate in water increases with increasing temperature and is shown in the table below.

Solubility of RbClO 4 in Water
Temperature [° C]	0	10	20th	25th	30th	40	50	60	70	80	90	100
Solubility [g / l]	5	6th	10	12	15th	23	35	48.5	67.2	92	127	180

Rubidium perchlorate is also almost insoluble in common organic solvents:

Solubility of RbClO 4 in organic solvents (given in g RbClO 4 in 100 g saturated solution at 25 ° C)
Methanol	0.060
Ethanol	0.009
n-propanol	0.006
n-butanol	0.002
Isobutanol	0.004
acetone	0.095
Ethyl acetate	0.0016

Rubidium perchlorate crystallizes in the orthorhombic crystal system in the space group Pbnm (space group no.62 , position 3) with the lattice parameters a = 749.0 pm, b = 926.9 pm and c = 581.4 pm, in the unit cell there are four formula units . At 279 ° C there is a phase transformation into a cubic crystal structure with a = 770 pm, in which four formula units are also arranged per unit cell. The crystals are isomorphic to the crystals of potassium perchlorate .

Chemical properties

When heated to red heat, rubidium perchlorate decomposes into rubidium chloride and oxygen.

${\displaystyle {\ce {RbClO4 -> RbCl + 2O2 ^}}}$

use

Due to its poor solubility, rubidium perchlorate can be used in addition to rubidium hexachloridoplatinate , rubidium hexafluoridosilicate and rubdium tetrafluoridoborate for the analytical separation of rubidium and potassium .

Individual evidence

1. ↑ ^{a b c d e f} Jean D'Ans, Ellen Lax: Pocket book for chemists and physicists. 3. Elements, inorganic compounds and materials, minerals, Volume 3. 4. Edition, Springer, 1997, ISBN 978-3-5406-0035-0 , p. 686 ( limited preview in the Google book search).
2. ↑ ^{a b} Data sheet rubidium perchlorate from AlfaAesar, accessed on June 18, 2010 ( PDF )(JavaScript required) .
3. ↑ Data sheet Rubidium perchlorate, anhydrous (PDF) from Strem, accessed on December 25, 2012.
4. ↑ ^{a b c} R. Abegg, F. Auerbach: Handbuch der inorganic Chemie , Verlag S. Hirzel, Vol. 2, 1908. P. 431; Full text .
5. ↑ ^{a b} data sheet Rubidium perchlorate from Sigma-Aldrich , accessed on April 22, 2011 ( PDF ).
6. ↑ Aterton Seidell: Solubilities Of Organic Compounds Vol - I , p. 1435; Full text .
7. ^ KA Hofmann: Textbook of Inorganic Chemistry , 2nd edition 1919. Verlag F. Vieweg & Sohn, p. 439; Full text .