Urea when heated a white residue is formed. Its alkaline solution when treated with few drops of ${\mathrm{CuSO}}_4$ solution gives:

1. Red colour

2. Violet colour

3. Green colour

4. Yellow colour

The diamide of carbonic acid is:

(1) acetamide

(2) formamide

(3) benzamide

(4) urea

The basic character of methylamines in vapour phase is:

(1) $3°>2°>1°>N{H}_3$

(2) $2°>3°>1°>{\mathrm{NH}}_3$

(3) $1°>2°>3°>{\mathrm{NH}}_3$

(4) None of these

Gabriel's phthalimide reaction is used to prepare:

(1) Primary amine

(2) Secondary amine

(3) Tertiary amine

(4) All of the above

Grignard reagent and acetyl chloride does not react with:

(1) ${\mathrm{RNH}}_2$

(2) ${\mathrm{R}}_2\mathrm{NH}$

(3) ${\mathrm{R}}_3\mathrm{N}$

(4) None of these

General formula of an amine is:

(1) ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+1}\mathrm{N}$

(2) ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+2}\mathrm{N}$

(3) ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+3}\mathrm{N}$

(4) ${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}}\mathrm{N}$

The amine may contain:

(1) $-{\mathrm{NH}}_2 \mathrm{gp}.$

(2) $\underset{\left|}{\overset{\right|}{\mathrm{N}}}\mathrm{H}$ gp.

(3) $-\underset{\left|}{\overset{\right|}{\mathrm{N}}}$ gp.

(4) all of these

Primary amine and secondary amine are distinguished by:

1. ${\mathrm{Br}}_2/\mathrm{KOH}$

2. HClO

3. ${\mathrm{HNO}}_2$

4. ${\mathrm{NH}}_3$

Which of the following is carbamide?

(1) ${\mathrm{CH}}_3{\mathrm{CONH}}_2$

(2) ${\mathrm{NH}}_2{\mathrm{CONH}}_2$

(3) ${\mathrm{CH}}_2\left({\mathrm{NH}}_2\right){\mathrm{CONH}}_2$

(4) $\mathrm{CO}\left(\mathrm{OH}\right){\mathrm{NH}}_2$

Reaction of primary amine with aldehydes gives:

(1) amide

(2) aldimine

(3) nitrile

(4) none of these