Magnesium tetrahydride borate

Magnesium tetrahydride borate
Magnesium tetrahydride borate
General
Systematic ; name	Magnesium tetrahydride borate
Traditional names	Magnesium borohydride; magnesium tetrahydroborate
Chem. formula	Mg [BH 4 ] 2
Physical properties
condition	colorless crystals
Molar mass	53.99 g / mol
Density	0.989; 1,046 g / cm³
Thermal properties
T. decomp.	305 ° C
Enthalpy of Education	-153 kJ / mol
Classification
Reg. CAS number	16903-37-0
PubChem
Reg. EINECS number
Smiles

Magnesium tetrahydride borate - an inorganic compound, a complex mixed hydride of magnesium and boron with the formula Mg [BH ₄ ] ₂ , colorless crystals, reacts with water.

Content

Getting

The interaction of diborane with magnesium hydride in ether:

{\mathsf {B_{2}H_{6}+MgH_{2}\ {\xrightarrow {\ }}\ Mg[BH_{4}]_{2}}}

{\ displaystyle {\ mathsf {B_ {2} H_ {6} + MgH_ {2} \ {\ xrightarrow {\}} \ Mg [BH_ {4}] _ {2}}}}

The reaction of magnesium chloride and lithium tetrahydride borate :

{\mathsf {2Li[BH_{4}]+MgCl_{2}\ {\xrightarrow {\ }}\ Mg[BH_{4}]_{2}+2LiCl}}

{\ displaystyle {\ mathsf {2Li [BH_ {4}] + MgCl_ {2} \ {\ xrightarrow {\}} \ Mg [BH_ {4}] _ {2} + 2LiCl}}}

Physical Properties

Magnesium tetrahydride borate forms colorless crystals of tetragonal syngony , space group I 4 ₁ cd , cell parameters a = 1.359 nm, c = 1.651 nm.

At a temperature of 186 ° C, it passes into the cubic phase , the cell parameters a = 1.55 nm.

Chemical Properties

Reacts with water:

{\mathsf {Mg[BH_{4}]_{2}+8H_{2}O\ {\xrightarrow {\ }}\ Mg(OH)_{2}+2B(OH)_{3}+8H_{2}\uparrow }}

{\ displaystyle {\ mathsf {Mg [BH_ {4}] _ {2} + 8H_ {2} O \ {\ xrightarrow {\}} \ Mg (OH) _ {2} + 2B (OH) _ {3} + 8H_ {2} \ uparrow}}}

Literature

Chemical Encyclopedia / Editorial Board: Knunyants I.L. et al. - M .: Soviet Encyclopedia, 1988. - T. 1. - 623 p.
Chemistry Handbook / Editorial: Nikolsky B.P. et al. - 3rd ed., rev. - L .: Chemistry, 1971. - T. 2. - 1168 p.