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The speed of sound in any chemical element in the fluid phase has one temperature ... 5 B boron; use: ... 28 Ni nickel; use: 6040: 3000: 4900: room temperature CRC:
Nickel(II) hydroxide is the inorganic compound with the formula Ni(OH) 2. It is a lime-green solid that dissolves with decomposition in ammonia and amines and is attacked by acids. It is electroactive, being converted to the Ni(III) oxy-hydroxide , leading to widespread applications in rechargeable batteries .
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 creates a pressure of up to 3.4 MPa. The main reactions can be summarized as 2 NaBH 4 ↔ 2NaH + B 2 H 6 2Ni + 2 B 2 H 6 + NaH ↔ Ni 2 B + 3 BH 3 + 2 H 2 + Na
Nickel boride is the common name of materials composed chiefly of the elements nickel and boron that are widely used as catalysts in organic chemistry. [1] [2] Their approximate chemical composition is Ni 2.5 B, [3] and they are often incorrectly denoted "Ni 2 B" in organic chemistry publications.
Nickel is a silvery-white metal with a slight golden tinge that takes a high polish. It is one of only four elements that are ferromagnetic at or near room temperature; the others are iron, cobalt and gadolinium. Its Curie temperature is 355 °C (671 °F), meaning that bulk nickel is non-magnetic above this temperature.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Nickel hydroxides are used in nickel–cadmium and Nickel–metal hydride batteries. Nickel(II) hydroxide Ni(OH) 2, the main hydroxide of nickel is coloured apple green. It is known as the mineral theophrastite. β-NiO(OH) is a black powder with nickel in the +3 oxidation state.
The standard Gibbs free energy of formation (G f °) of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states (the most stable form of the element at 1 bar of pressure and the specified temperature, usually 298.15 K or 25 °C).