181.
Identify reactant $$(X)$$ in the given reaction sequence.
A
$$C{H_3}MgCl$$
B
$$C{H_3}COCl + Mg$$
C
$$MgC{l_2}$$
D
$$C{H_3}C{H_2}MgCl$$
Answer :
$$C{H_3}MgCl$$
182.
\[\left( P \right)\xrightarrow[\Delta ]{EOH}\] 
\[\left( Q \right)\xrightarrow[\Delta ]{EOH}Ph-C{{H}_{2}}-OH+Ph-C{{O}_{2}}\]
\[\left( R \right)\xrightarrow{{{O}_{3}}}P+Q,\] Structure of $$(R)$$ is:
A
B
C
D
Answer :
183.
In this reaction,
$$C{H_3}CHO + HCN \to $$ \[C{{H}_{3}}CH\left( OH \right)CN\xrightarrow{H.OH}\] $$C{H_3}CH\left( {OH} \right)COOH$$
an asymmetric centre is generated. The acid obtained would be
A
$$50\% \,D + 50\% \,L{\text{ - isomer}}$$
B
$$20\% \,D + 80\% \,L{\text{ - isomer}}$$
C
$$D{\text{ - isomer}}$$
D
$$L{\text{ - isomer}}$$
Answer :
$$50\% \,D + 50\% \,L{\text{ - isomer}}$$
184.
Identify the products $$(X)$$ and $$(Y)$$ in the given reaction:
\[\xrightarrow[AlC{{l}_{3}}]{{{\left( C{{H}_{3}}CO \right)}_{2}}O}X\xrightarrow[\text{conc}.\,{{H}_{2}}S{{O}_{4}}]{\text{conc}.\,HN{{O}_{3}}}Y\]
A
$$X =$$ Acetophenone, $$Y =$$ $$m$$ - Nitroacetophenone
B
$$X =$$ Toluene, $$Y =$$ $$m$$ - Nitroacetotoluene
C
$$X =$$ Acetophenone, $$Y = o$$ and $$p$$ - Dinitroacetophenone
D
$$X =$$ Benzaldehyde, $$Y =$$ $$m$$ - Nitrobenzaldehyde
Answer :
$$X =$$ Acetophenone, $$Y =$$ $$m$$ - Nitroacetophenone
185. Aldehydes other than formaldehyde react with Grignard reagent to give addition products which on hydrolysis give
A
tertiary alcohols
B
secondary alcohols
C
primary alcohols
D
carboxylic acids
Answer :
secondary alcohols
186. An organic compound $$X$$ having molecular formula $${C_5}{H_{10}}O$$ yields phenyl hydrazone and gives negative response to the iodoform test and Tollen's test. It produces $$n$$ - pentane on reduction. $$X$$ could be
A
pentanal
B
2 - pentanone
C
3 - pentanone
D
$$n$$ - amyl alcohol
Answer :
3 - pentanone
187.
\[\xrightarrow{{{H}^{+}}}X,\] most likely the compound $$X$$ is
A
B
C
D
Answer :
188. Which compound is obtained when acetaldehyde is treated with dilute solution of caustic soda?
A
Sodium acetate
B
Resinous mass
C
Aldol
D
Ethyl acetate
Answer :
Aldol
189. The best oxidising agent for oxidation of $$C{H_3} - CH = CH - CHO$$ to $$C{H_3} - CH = CH - COOH$$ is
A
Baeyer's reagent
B
Tollens' reagent
C
Schiff's reagent
D
acidified dichromate
Answer :
Tollens' reagent
190.
the shown polymer is obtained when a carbonyl compound is allowed to stand. It is a white solid. The polymer is
A
trioxane
B
$$para$$ - formaldehyde
C
formose
D
$$meta$$ - aldehyde
Answer :
trioxane
