An unknown compound A has a molecular formula C₄H₆. When A is treated with excess of Br₂ a new substance B with formula C₄H₆Br₄ is formed. A forms a white ppt. with ammoniacal silver nitrate solution. A may be-

1. But-1-yne

2. But-2-yne

3. But-1-ene

4. But-2-ene

The appropriate reagent for the following transformation,

  is :

(1) Zn(Hg),HCl

(2) NH₂NH₂, OH^-

(3) H₂/Ni

(4) NaBH₄

Which compound would give 5-keto-2-methyl hexanal upon ozonolysis?

1.		2.
3.

The reduction of an alkyne to alkene using Lindlar's catalyst results into:

(1) cis-addition of hydrogen atoms

(2) trans-addition of hydrogen atoms

(3) a mixture obtained by cis- and trans-additions of hydrogen which are in equilibrium with each other

(4) a mixture obtained by cis- and trans-additions of hydrogen atoms which are not in equilibrium with each other.

Identify Z in the sequence,

$\mathrm{CH}3-{\mathrm{CH}}_2-\mathrm{CH}={\mathrm{CH}}_2\stackrel{\mathrm{HBr}/{\mathrm{H}}_2{\mathrm{O}}_2}{\to }\mathrm{Y}\stackrel{{\mathrm{C}}_2{\mathrm{H}}_5{\mathrm{O}}^{-}-{\mathrm{Na}}^{+}}{\to }\mathrm{Z}:$

1. $\mathrm{CH}3-\underset{{\mathrm{CH}}_3}{\underset{\mathrm{I}}{\mathrm{CH}}}-{\mathrm{CH}}_2-\mathrm{O}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$

2. $\mathrm{CH}3-{\mathrm{CH}}_2-\underset{{\mathrm{CH}}_3}{\underset{\mathrm{I}}{\mathrm{CH}}}-{\mathrm{CH}}_2-\mathrm{O}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$

3. ${\mathrm{CH}}_3-({\mathrm{CH}}_2{)}_3-\mathrm{O}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$

4. ${\mathrm{CH}}_3-({\mathrm{CH}}_2{)}_4-\mathrm{O}-{\mathrm{CH}}_3$

Acetylene can be converted to higher alkyne using the following sequence of reactions:

(1) Na,RX

(2) RMg X,R X

(3) either of these two

(4) none of these

$\mathrm{R}-\mathrm{COOH}$$\to$RCH₂OH. This mode of reduction can be effected only by:

1. NaBH₄

2. KMnO₄

3. LiAIH₄

4. All of the above

Propene, CH₃-CH=CH₂ can be converted into 1-propanol by oxidation. Which set of reagents among the following is ideal to effect the conversion?

(1) Alkaline KMnO₄

(2) B₂H₆ and alk. H₂O₂

(3) O₃/zinc dust

(4) OsO₄/CHCl₃

CH₃CH=CHCHO is oxidized to CH₃CH=CHCOOH using-

1. Alkaline permanganate

2. Ammoniacal silver nitrate

3. Selenium dioxide

4. Osmium tetraoxide

An alkene, obtained by the dehydration of an alcohol(A), on ozonolysis gives two molecules of acetaldehyde for every molecule of alkene. the alcohol (A) is:

1. ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{OH}$

2. ${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{OH}$

3. ${\mathrm{CH}}_3\mathrm{CH}={\mathrm{CHCH}}_2\mathrm{OH}$

4. ${\mathrm{CH}}_3{\mathrm{CH}}_2\underset{\mathrm{OH}}{\underset{\mathrm{I}}{\mathrm{CH}}}{\mathrm{CH}}_3$