Organic chemistry-some basic principles and techniques practice · Medium

The correct answer is C (If Assertion is True but the Reason is False) because while Eu²⁺ and Yb²⁺ are indeed reducing agents, the reason is due to their tendency to achieve stable f⁷ and f¹⁴ configurations, respectively, not a half-filled configuration.

The element X could have an atomic weight of 7 and its oxide is ${\mathrm{X}_2}\mathrm{O}$ because the ratio of their masses is consistent with this.

Option B ($KCl_3 + F_2 \rightarrow KF_3 + Cl_2$) is incorrect because fluorine does not form $F_3^−$ due to the absence of available d-orbitals for expansion of its octet.

Option A (Aniline) is correct because aniline, being an organic compound immiscible with water and having a high boiling point, can be effectively purified by steam distillation.

Option C (2 and 4) is correct because the compound has two asymmetric carbon atoms, leading to $2^2 = 4$ stereoisomers.

Option B is correct because in chlorobenzene solution, the basic strength of amines increases with the number of ethyl groups due to the +I effect, making the order $1^{\circ} < 2^{\circ} < 3^{\circ}$.

The correct answer is A (4) because the molecule has one chiral center, leading to two enantiomers, and exhibits geometrical isomerism (cis/trans), resulting in a total of 4 stereoisomers.

Option A (4,3,1) is correct because there are four structural isomers of primary amines, three of secondary amines, and one of tertiary amines with the formula C₄H₁₁N.

Option D (-OH) is correct because it exhibits +M effect due to lone pairs on oxygen and -I effect due to the high electronegativity of oxygen.

Option B (Ethyl-2-butenoate) is correct because it correctly identifies the ester functional group and the position of the double bond in the carbon chain.

Option A (0.84) is correct because the percentage of nitrogen is calculated using the formula involving the normality of the acid, its volume, and the weight of the food sample.

Option B (Ammonia) is correct because alkyl groups are electron-donating, increasing basicity, and ammonia has no alkyl groups.

Option B is the correct IUPAC structure because it correctly represents 2,2-Dibromo-1-phenylpentane with the bromine atoms on the second carbon and the phenyl group on the first carbon of the pentane chain.

Option D (Phenanthrene) is correct because phenanthrene has more resonance structures compared to the other options, leading to higher resonance energy.

Option B (${CuO}$) is correct because copper(II) oxide is used to oxidize carbon to carbon dioxide and hydrogen to water in the detection of carbon and hydrogen in organic compounds.