chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
of
nickel
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to ...
and
boron
Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has th ...
with
formula
In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwee ...
. It is one of the borides of nickel.
The formula "" and the name "nickel boride" are often used for a nickel-boron catalyst obtained by reacting nickel salts with sodium borohydride. However, that product is not a well-defined compound, and its bulk formula is closer to (sic).
Synthesis
Dinickel boride can be obtained (together with other nickel borides) by heating sodium borohydride with powdered nickel metal up to 670 °C in a closed vessel, so that the released
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...
creates a pressure of up to 3.4 MPa. The main reactions can be summarized as
: 2 ↔ 2NaH +
: 2Ni + 2 + NaH ↔ + 3 + 2 + Na
but other reactions occur, yielding other borides.