Stephen's reduction is used to prepare aldehyde from

• alcohol

• alkyl cyanides

• alkanones

• acid chlorides

Given below are some statements concerning formic acid, which of them is true ?

• It is weaker acid than acetic acid

• It is reducing agent

• When its calcium salt is heated, it forms a ketone

• It is an oxidising agent

93.

Which of the following gives oxalic acid?

• Heating of acetic acid

• Action of nitric acid on glucose

• Acidic hydrolysis of cyanogen

• Strong heating of sodium formate

Benzene diazonium chloride on reaction with phenol in weakly basic medium gives

• diphenyl ether

• p-hydroxy azobenzene

• chlorobenzene

• benzene

Hinsberg's reagent is

• C₆H₅COCl

• CH₃COCl

• C₆H₅CH₂Cl

• C₆H₅SO₂Cl

Reaction of aniline with benzaldehyde is

• substitution

• addition

• condensation

• polymerisation

In the following reaction,$\mathrm{X} \stackrel{\mathrm{bromination} }{\to }\mathrm{Y}\underset{+\mathrm{HCl}}{\overset{{\mathrm{NaNO}}_2}{\to }}\mathrm{Z}\underset{{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}}{\overset{\mathrm{boiling}}{\to }}\mathrm{tribomo} \mathrm{benzene} \mathrm{X} \mathrm{is}$

• benzoic acid

• salicylic acid

• phenol

• aniline

Brown ring is made for

• NO^-₃

• Cl^-

• I^-

• Br^-

Nessler's reagent is used to detect

• ${\mathrm{CrO}}_4^{2-}$

• ${\mathrm{PO}}_4^{3-}$

• ${\mathrm{MnO}}_4^{-}$

• ${\mathrm{NH}}_4^{+}$

Glycerol, on heating with oxalic acid at 110$°$C gives

• ethanol

• methanoic acid

• ether

• acetone