Question

Raney nickel, which is used as a catalyst, is obtained:
A.By grinding solid nickel
B.By treating nickel aluminum alloy with dilute NaOH
C.By treating nickel aluminum alloy with dilute HCl
D.By heating nickel tetracarbonyl.

Answer 1

As we know that the raney nickel is also known as spongy nickel. And it is solid and thin-grained in nature. The raney nickel is mainly used as a solid catalyst in the reactions. And the raney nickel is an alloy which contains aluminium and nickel. And so much aluminum is eliminated by using a leaching process. And this reagent is widely used as a reagent in the hydrogenation process.

Complete answer:
When the solid nickel is grained, there will not be a formation of raney nickel reagent. Hence, option (A) is incorrect.
The raney nickel is widely used as a reagent in organic chemistry and it can be prepared by treating nickel aluminum alloy with dilute sodium hydroxide. And this treatment is known as activation. And after this activation process, a porous structure will be left and it will have a large surface area and its catalytic activity will be very high.
Let’s see the chemical equation of preparation,
$Al + Ni\xrightarrow{{1200 - {{1500}^o}C}}Al - Ni$
$Al - Ni\xrightarrow[{ - NaAl{O_2}}]{}Ni$
Hence, option (B) is correct.
If the nickel aluminum alloy is treated with dilute hydrochloric acid, there will not be a formation of raney nickel catalyst. Hence, option (C) is correct.
If the nickel tetracarbonyl is heated, it will be dissociated and there will be a formation of corresponding components. Hence, the option (D) is correct.

Note:
We must have to know that the raney nickel is a common catalyst which is used in most of the reactions in organic chemistry. And it can be prepared by the activation process. And that is, the nickel aluminum alloy is treated with dilute sodium hydroxide and there is a formation of raney nickel. And the formula of raney nickel is ‘Ni’. And this catalyst can be used for the reduction process.