Organic Chemistry PYQ — Page 5

Consider all the structural isomers with molecular formula $\mathrm{C}_{5} \mathrm{H}_{11} \mathrm{Br}$ are separately treated with $\mathrm{KOH}(\mathrm{aq})$ to give respective substitution products, without any rearrangement. The number of products which can exhibit optical isomerism from these is $\_\_\_\_$.

In an estimation of sulphur by Carius method $0.2$ g of the substance gave $0.6$ g of BaSO$_4$. The percentage of sulphur in the substance is _____ %. (Given molar mass in g mol$^{-1}$ S : $32$, BaSO$_4$ : $233$)

The following structures are 

Match the LIST-I with LIST-II \(\begin{array}{|c|l|c|l|} \hline & \textbf{List-I (Reagents)} & & \textbf{List-II (Name of reaction} \\ & & & \textbf{involving carbonyl compounds)} \\ \hline A. & \mathrm{NH_2{-}NH_2,\ KOH} & I. & \text{Tollen's Test} \\ \hline B. & \mathrm{Ag(NH_3)_2OH} & II. & \text{Clemmensen Reduction} \\ \hline C. & \begin{array}{l} \text{Aq. } \mathrm{CuSO_4}, \\ \text{Sodium potassium} \\ \text{tartarate, KOH} \end{array} & III. & \text{Wolff--Kishner Reduction} \\ \hline D. & \mathrm{Zn{-}Hg,\ HCl} & IV. & \text{Fehling's Test} \\ \hline \end{array}\) Choose the correct answer from the options given below:

Identify the correct IUPAC name of hydrocarbon ($x$) containing three primary carbon atoms and with molar mass $72\text{ g mol}^{-1}$.

Consider the following reaction.  Statement I : In the above reaction, product formed will be a mixture of benzyl alcohol and iodobenzene. Statement II : In the above reaction, the $-\text{O}-\text{CH}_2-$ bond is cleaved to give the product. In the light of the above statements, choose the correct answer from the options given below :

 The correct sequence of reagents for the above conversion of X to Y is :

The compound (X) on (i) on heating in the presence of anhydrous $AlCl_3$ and HCl gas gives $2,4$-dimethyl pentane (ii) aromatization gives toluene and (iii) cyclisation gives methyl cyclohexane The correct name of compound (X) is:

When 1 g of compound $(\mathrm{X})$ is subjected to Kjeldahl's method for estimation of nitrogen, 15 mL 1 M $\mathrm{H}_{2} \mathrm{SO}_{4}$ was neutralized by ammonia evolved. The percentage of nitrogen in compound $(\mathrm{X})$ is :

The total number of aromatic compounds/species from the following is 

Compound ' P ' undergoes the following sequence of reactions :  ' $\mathrm{P}^{\prime}$ is :

Given below are two statements: Statement I: Cross aldol condensation between two different aldehydes will always produce four different products. Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only. In the light of the above statements, choose the correct answer from the options given below

Given below are two statements for the following reaction sequence.  Statement I: Compound ' $Z$ ' will give yellow precipitate with NaOI. Statement II: Compound ' Q ' has two different types of ' H ' atoms (aromatic : aliphatic) in the ratio 1:3. In the light of the above statements, choose the correct answer from the options given below:

Given below are two statements : Statement I: The condensation reaction between $CH_3-CH=O$ and $H_2N-NH-C(=O)-NH_2$ under optimum pH will produce $CH_3-CH=N-N(H)-C(=O)-NH_2$. Statement II: The molecule, $Ph-CH(O-H)(O-CH_3)$ will generate $Ph-CH=O$ in the presence of dilute acid. In the light of the above statements, choose the correct answer from the options given below :

One mole of phenol is treated with dilute HNO$_3$ at $298$ K to give a mixture of products. The mixture is separated by steam distillation. The steam volatile compound (X) is separated. The increase in percentage of oxygen in (X) with respect to phenol is _____ $\times 10^{-1}$ % (Given molar mass in g mol$^{-1}$ H:$1$, C:$12$, N:$14$, O:$16$)

Consider the following reactions giving major product. Identify the correct reaction.

Given below are two statements: Statement I: $3$-phenylpropene reacts with HBr and gives secondary alkyl bromide having a chiral carbon atom as the major product. Statement II: Aryl chlorides and aryl cyanides can be prepared by Sandmeyer reaction as well as Gattermann reaction. In the light of the above statements, choose the correct answer from the options given below

Given below are two statements : Statement (I) : Benzyl chloride reacts faster in $S_N1$ mechanism than ethyl chloride. Statement (II) : Ethyl carbocation intermediate is less stabilized by hyperconjugation than benzyl carbocation by resonance. In the light of the above statements, choose the correct answer from the options given below :

An optically active alkyl bromide C$_4$H$_9$Br, reacts with ethanolic KOH to form major compound [A] which reacts with bromine to give compound [B]. Compound [B] reacts with ethanolic KOH and sodamide to give compound [C]. One molecule of water adds to compound [C] on warming with mercuric sulphate and dilute sulphuric acid at $333$ K to form compound [D]. The functional group in compound D will be confirmed by :

In IUPAC nomenclature, the correct order of decreasing priority of functional group is :

A student is given one compound among the following compounds that gives positive test with Tollen's reagent.  The compound is :

Identify the correct statements. A. Glucose exists in two anomeric forms. B. Anomers of glucose differ in configuration at C$-1$ in cyclic hemiacetal structure. C. Melting point of $\alpha$-anomer of glucose is greater than $\beta$-anomer. D. Specific rotation of $\alpha$-anomer is $+19°$ while for $\beta$-anomer is $+112°$ E. $\alpha$ and $\beta$-anomers of glucose are prepared by crystallization of saturated glucose solution at $303$ K and $371$ K respectively. Choose the correct answer from the options given below:

Iodoform test can differentiate between A. Methanol and Ethanol B. $\mathrm{CH}_{3} \mathrm{COOH}$ and $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COOH}$ C. Cyclohexene and cyclohexanone D. Diethyl ether and Pentan-3-one E. Anisole and acetone Choose the correct answer from the options given below:

Identify compounds A and E in the following reaction sequence.