Organic chemistry-some basic principles and techniques practice · Easy

Option C (3) is correct because a ketone requires a carbonyl group (C=O) bonded to two other carbon atoms, making the smallest ketone acetone (CH3COCH3).

Option A (Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A)) is correct because the dipole moment is directly proportional to the electronegativity difference between the bonded atoms.

Option B (Position isomers) is correct because the position of the amino group ($NH_2$) is different in the two structures.

Option D (Carbine) is correct because a carbene is a neutral divalent carbon species with two unshared electrons.

Option B (Urea) is correct because Friedrich Wöhler synthesized urea from ammonium cyanate, an inorganic compound.

Option C (Electromeric effect) is correct because the electromeric effect involves the complete transfer of a shared pair of electrons to one of the atoms joined by a multiple bond upon the approach of a reagent.

Option B ($\mathrm{C}{\mathrm{u}^{2 + }}$) is correct because Benedict's solution contains copper(II) ions (Cu2+), which are responsible for the color change when reducing sugars are present.

Option B (A nucleophile) is correct because the hydride ion (H-) has a lone pair of electrons and donates them to electron-deficient species.

Option A (1-butene-3-yne) is correct because it follows the IUPAC naming rules, prioritizing the double bond and numbering the carbon chain to give the lowest possible numbers to the multiple bonds.

Option B (Temporary effect) is correct because the electromeric effect occurs only in the presence of an attacking reagent and disappears when the reagent is removed.

Option B ($C{H_2} = CH - C \equiv CH$) is correct because the hybridization of the carbon atoms from left to right is $S{P^2},S{P^2},SP,SP$.

Option A ((ii) and (iii)) is correct because these molecules contain carbon atoms with both sp2 and sp hybridization.

Option C is correct because according to IUPAC nomenclature, ${\mathrm{C}_6}{\mathrm{H}_5}\mathrm{COCl}$ is named as Benzene carbonyl chloride.

Option D (α-chloropropionic acid) is correct because it contains a chiral carbon atom, which is a carbon atom bonded to four different groups, making it optically active.

Option C is correct because stereoisomers have the same molecular and structural formula but differ in spatial arrangement, and cis/trans but-2-ene exemplify this.

Option B (2) is correct because C3H6 has two structural isomers: propene and cyclopropane.

Option A ($- \mathrm{COOH}$) is correct because carboxylic acid groups are electron-withdrawing and exhibit a -I effect.

Option A is correct because the second carbon in CH3CHClCOOH is bonded to four different groups (H, Cl, CH3, COOH), making it a chiral center.

Option C (pentanoic acid and 2 – methyl butanoic acid) is correct because they have the same molecular formula but differ in the arrangement of the carbon chain.

Option A ($\mathrm{C} - \mathrm{H}$) is correct because the C-H bond generally has the highest bond energy among the given options due to the smaller size and higher electronegativity of hydrogen.

Option A (Oyl halide) is correct because the IUPAC suffix for acyl halides (-COX) is 'oyl halide'.

Option B ($C{H_2} = CH - C \equiv CH$) is correct because it correctly assigns $SP^2$, $SP^2$, $SP$, and $SP$ hybridization to the carbon atoms from left to right.

Option A (44 kJ $\mathrm{mo}{\mathrm{l}^{ - 1}}$) is correct because the energy difference between the chair and boat form of cyclohexane is 44 kJ $\mathrm{mo}{\mathrm{l}^{ - 1}}$.

Option C (same physical property) is correct because while homologous series share the same functional group, chemical properties, and general formula, their physical properties vary due to differences in molecular weight.

Option C (Both (a) and (b)) is correct because both lead acetate and sodium nitroprusside can be used to detect the presence of sulfur in a sodium extract.

Option C (Brown ring test) is correct because the brown ring test is a confirmatory test for nitrates, not a preliminary test.

Option B (Thiocyanate) is correct because when an organic compound containing both nitrogen and sulfur is fused with sodium, it forms sodium thiocyanate (NaSCN).

Option A (Functional) is correct because acetic acid and methyl formate have different functional groups (carboxylic acid and ester, respectively).

The correct answer is C ($\mathrm{CH}_3-\mathrm{C} \equiv \mathrm{N}$) because the carbon atom bonded to the nitrogen atom is sp hybridized, not sp2.

Option C (Chromatography) is correct because chromatography is a technique used to separate sugars based on their different affinities for a stationary and mobile phase.