Test for Nickel(II) Ion

A reagent used to test nickel ion is ______.

Cotyledons are also called-

Why is ammonium chloride added to the solution during the precipitation of Nickel $\left(\mathrm{II}\right)$ ion with hydrogen sulphide?

Why ${\mathrm{H}}_2\mathrm{S}$ is passed after addition ${\mathrm{NH}}_4\mathrm{Cl}$ and ${\mathrm{NH}}_4\mathrm{OH}$?

In the cyanide test for nickel, what is the colour of the precipitate formed?

Which of the following complexes is formed during the cyanide test for nickel(II) ions?

What type of reaction occurs between nickel ions and bromine water during the test?

Which colour precipitate is observed when bromine water and excess of $\mathrm{NaOH}$reacts with a solution containing nickel ions?

A solution when treated with dimethyl glyoxime gives a rosy red complex. The metal present is

Dimethyl glyoxime forms a coloured complex with