Which of the following substances does not give the iodoform test?

$p-$chloroaniline and anilinium hydrochloride can be distinguished by

For the identification of $\beta$-naphthol using dye test,it is necessary to use :

The Nessler's reagent contains

Nitroso amines $(R_2N - N = O)$ are soluble in water. On heating them with concentrated $H_2SO_4$,they give secondary amines. The reaction is called:

Carbylamine test is shown by