What amount will be credited to the Income and Expenditure Account for the year 2023-24 for subscriptions?

₹4,85,000. Subscription for the year = Total Received - Received for Previous Year - Received for Next Year + Outstanding for Current Year = ₹5,00,000 - ₹25,000 - ₹40,000 + ₹50,000 (i.e., ₹55,000 - ₹5,000 irrecoverable).

What is the corrective action if the partnership deed is silent on interest on drawings but the accountant charged 6%?

Credit P's, Q's, and R's Capital Accounts with the interest wrongly debited. When the deed is silent, no interest is charged.

What happens in a Common-Size Income Statement if the percentage of 'Cost of Revenue from Operations' to 'Revenue' increases?

It indicates a deterioration in gross profit margin, as a larger portion of revenue is being consumed by costs.

CUET Chemistry Mock Test 9 Solutions & Explanations

Q1. When crystalline NaCl is heated in an atmosphere of sodium vapor, it turns yellow. This phenomenon is due to:

Correct Answer: Option A (The formation of a solid solution of Na in NaCl.)

Explanation: ΔTb = i × Kb × m. For MgCl₂, i=3. For Urea, i=1. Ratio = (i₁m₁)/(i₂m₂) = (3 × 0.1) / (1 × 0.2) = 0.3 / 0.2 = 3/2 or 1.5:1.
* Concept: Solutions (Colligative Properties, van't Hoff factor).
* Type: Application-based Numerical.

Q2. Consider two aqueous solutions: (I) 0.1 M MgCl₂ and (II) 0.2 M Urea. Assuming complete dissociation for the electrolyte, what is the approximate ratio of the elevation in boiling point of solution (I) to that of solution (II)? (Kb is the same for both)

Correct Answer: Option D (2 : 3)

Explanation: To find Λ°m for a weak acid (CH₃COOH), you need three strong electrolytes. NH₄OH is a weak base, so its Λ°m cannot be easily determined, making this set ineffective for the calculation.
* Concept: Electrochemistry (Kohlrausch's Law).
* Type: Conceptual Application.

Q3. To determine the molar conductivity at infinite dilution (Λ°m) for acetic acid (CH₃COOH) using Kohlrausch's law, which of the following sets of electrolytes would be LEAST effective or incorrect to use?

Correct Answer: Option C (H₂SO₄, (CH₃COO)₂Ba, BaCl₂)

Explanation: The reaction is Rate = k[Ester][H₂O]. For it to be pseudo-first-order, the concentration of one reactant (H₂O) must be in such large excess that it does not change significantly during the reaction, making Rate ≈ k'[Ester].
* Concept: Chemical Kinetics (Pseudo-first-order reaction).
* Type: Expected Type, Conceptual.

Q4. In the acid-catalyzed hydrolysis of ethyl acetate, which is a pseudo-first-order reaction, what is the key condition that must be maintained for the reaction to follow first-order kinetics with respect to the ester?

Correct Answer: Option C (The concentration of water must be significantly large and remain virtually constant.)

Explanation: These are linkage isomers. The metal is bonded to NO₂ via Nitrogen in one and via Oxygen in the other. These different bonds (M-NO₂ vs M-ONO) will show characteristic and different absorption frequencies in the IR spectrum.
* Concept: Coordination Compounds (Isomerism, Spectroscopy).
* Type: PYQ-based, Application.

Q5. A coordination complex exists in two forms, [Co(NH₃)₅(NO₂)]Cl₂ and [Co(NH₃)₅(ONO)]Cl₂. The most definitive experimental method to distinguish between these two isomers would be:

Correct Answer: Option B (X-ray crystallography to determine bond lengths)

Explanation: The complete hydrolysis of XeF₆ is: XeF₆ + 3H₂O → XeO₃ + 6HF. XeO₃ has a trigonal pyramidal geometry due to one lone pair and three bond pairs on the central Xe atom.
* Concept: p-Block Elements (Noble Gas Compounds).
* Type: Tricky Recall.

Q6. Complete and controlled hydrolysis of Xenon hexafluoride (XeF₆) results in the formation of a specific xenon compound. Identify the final product and its geometry.

Correct Answer: Option C (XeO₂, Linear)

Explanation: (A) Toluene → Friedel-Crafts Acylation → (B) p-Methylacetophenone → Clemmensen Reduction → (C) p-Ethyltoluene → Strong Oxidation → (D) Terephthalic acid (benzene-1,4-dicarboxylic acid). The entire alkyl side chain is oxidized.
* Concept: Organic Chemistry (Multi-step Synthesis).
* Type: Application-based.

Q7. An organic compound 'A' (C₇H₈) reacts with CH₃COCl in the presence of anhydrous AlCl₃ to give 'B'. 'B' on treatment with Zn-Hg/HCl gives 'C'. 'C' on oxidation with alkaline KMnO₄ gives 'D'. Identify 'D'.

Correct Answer: Option C (Terephthalic acid)

Explanation: In an acidic or neutral solution, Mn(+6) in MnO₄²⁻ is unstable and disproportionates into Mn(+7) in MnO₄⁻ and Mn(+4) in MnO₂.
* Concept: d-Block Elements (Redox Chemistry).
* Type: Conceptual.

Q8. In an acidic aqueous solution, the manganate ion (MnO₄²⁻) is unstable and undergoes a reaction. Which statement correctly describes this transformation?

Correct Answer: Option A (It is oxidized to permanganate ion (MnO₄⁻).)

Explanation: In the gaseous phase, solvation effects are absent. Basicity depends only on the +I effect and resonance. Cyclohexylamine (I) is most basic (aliphatic, no delocalization). Aniline (II) is least basic (lone pair delocalized). For substituted anilines, the +I effect of methyl groups increases basicity (IV > III > II).
* Concept: Organic Chemistry (Basicity of Amines).
* Type: Tricky Conceptual.

Q9. Arrange the following compounds in the correct decreasing order of their basic strength in the gaseous phase: Cyclohexylamine (I), Aniline (II), N-methylaniline (III), N,N-dimethylaniline (IV).

Correct Answer: Option D (II > III > IV > I)

Explanation: Maltose is specifically formed by the condensation between the C1 of one α-D-glucose and the C4 of another α-D-glucose. The anomeric carbon (C1) is in the α-configuration.
* Concept: Biomolecules (Carbohydrate Structure).
* Type: Factual/Conceptual.

Q10. The disaccharide maltose is composed of two α-D-glucose units. Which statement accurately describes the glycosidic linkage present in it?

Correct Answer: Option B (A C1-C4 glycosidic linkage between a glucopyranose and a fructofuranose unit.)

Explanation: On an Ellingham diagram, a lower line indicates a more stable oxide. For a metal oxide to be reduced by an element, the ΔG° line for the reducing agent must be below the line of the metal oxide. Here, C reducing ZnO is spontaneous.
* Concept: Metallurgy (Ellingham Diagram).
* Type: High-level Conceptual.

Q11. According to the Ellingham diagram, at a specific high temperature (T > 1073 K), the ΔG° line for the reaction 2C(s) + O₂(g) → 2CO(g) lies below the line for 2Zn(s) + O₂(g) → 2ZnO(s). What is the primary metallurgical implication of this?

Correct Answer: Option B (Carbon (coke) can be effectively used to reduce zinc oxide to zinc.)

Explanation: Acidity order: p-Nitrophenol (strong -R) > Phenol > p-Methoxyphenol (weak +R) > p-Cresol (weak +I/+H). Since pKa is inversely proportional to acidity, the pKa order is the reverse: II < I < IV < III.
* Concept: Organic Chemistry (Acidity of Phenols).
* Type: Expected Type, Conceptual.

Q12. The pKa value is a measure of the acidity of a compound (lower pKa means stronger acid). What is the correct increasing order of pKa values for the following compounds: Phenol (I), p-Nitrophenol (II), p-Cresol (III), p-Methoxyphenol (IV)?

Correct Answer: Option C (III < IV < I < II)

Explanation: Glyptal is a polyester formed by the condensation of a dicarboxylic acid (Phthalic acid) and a diol (Ethylene glycol).
* Concept: Polymers (Condensation Polymerization).
* Type: Factual Recall.

Q13. The thermosetting polymer Glyptal, used in paints and lacquers, is formed by the condensation polymerization of which pair of monomers?

Correct Answer: Option D (Adipic acid and Hexamethylenediamine)

Explanation: The Langmuir model is based on the formation of a chemical-like monolayer on specific sites, after which no further adsorption occurs. The Freundlich model is an empirical formula that does not preclude multilayer adsorption.
* Concept: Surface Chemistry (Adsorption Isotherms).
* Type: Conceptual Comparison.

Q14. Which of the following statements is a fundamental assumption of the Langmuir adsorption isotherm but NOT of the Freundlich adsorption isotherm?

Correct Answer: Option B (The extent of adsorption increases with an increase in pressure.)

Explanation: The purpose of a salt bridge is to maintain electrical neutrality without reacting with the ions in the half-cells. Cl⁻ from KCl would precipitate Ag⁺ as AgCl (Ksp is very low), disrupting the cell's equilibrium and function.
* Concept: Electrochemistry (Galvanic Cells).
* Type: Practical Application.

Q15. In the construction of a galvanic cell involving a Ag⁺/Ag half-cell, a salt bridge containing KCl solution is avoided. What is the most probable reason for this precaution?

Correct Answer: Option C (KCl is a weak electrolyte and cannot function effectively in a salt bridge.)

Explanation: High-spin d⁶ in an octahedral field means weak field ligand. The configuration is t₂g⁴ eg². This gives 4 unpaired electrons. Magnetic Moment (μ) = √n(n+2) = √4(4+2) = √24 ≈ 4.90 BM.
* Concept: Coordination Compounds (Crystal Field Theory, Magnetic Properties).
* Type: Application-based Numerical.

Q16. What is the calculated spin-only magnetic moment (in Bohr Magnetons, BM) for a high-spin d⁶ metal ion in an octahedral field?

Correct Answer: Option C (4.90 BM)

Explanation: Sₙ1 reactivity depends on the stability of the carbocation intermediate. C₆H₅-CH⁺(CH₃) is a secondary benzylic carbocation, which is highly stabilized by resonance with the benzene ring and the +I effect of the methyl group, making it the most stable among the options.
* Concept: Organic Chemistry (Reaction Mechanisms, Sₙ1).
* Type: Conceptual Application.

Q17. Which of the following alkyl halides would exhibit the highest reactivity towards an Sₙ1 reaction?

Correct Answer: Option C (C₆H₅-CH(CH₃)-Br)

Explanation: Ranitidine is an H₂-receptor antagonist. It blocks the action of histamine on the H₂ receptors in the stomach's parietal cells, which are responsible for promoting acid secretion. It is thus classified as an antihistamine.
* Concept: Chemistry in Everyday Life (Drugs Classification).
* Type: Factual Application.

Q18. Ranitidine (Zantac) is a widely used medicine. It functions by preventing the interaction of a specific chemical with receptors present in the stomach wall, thereby reducing acid secretion. To which class of drugs does it belong?

Correct Answer: Option C (Antihistamine)

Explanation: The pyrosulfate ion is formed by heating sulfates, causing two SO₄ tetrahedra to join by sharing an oxygen atom, forming a characteristic S-O-S bridge. Its parent acid is pyrosulfuric acid (oleum).
* Concept: p-Block Elements (Structure of Oxoacids).
* Type: Structural Conceptual.

Q19. The structure of several oxoacids of sulfur is based on a tetrahedron around the sulfur atom. Which of the following species contains a direct S—O—S linkage?

Correct Answer: Option D (Dithionite ion (S₂O₄²⁻))

Explanation: Negative deviation means A-B interactions are stronger than A-A/B-B interactions. This leads to lower vapor pressure than predicted and an exothermic mixing (ΔH_mix < 0). Such solutions form a maximum boiling azeotrope, where escaping from the liquid phase is more difficult.
* Concept: Solutions (Non-ideal solutions, Azeotropes).
* Type: High-level Conceptual.

Q20. A binary liquid mixture of acetone and chloroform exhibits a negative deviation from Raoult's law. Which of the following is a direct consequence of this behavior?

Correct Answer: Option A (The A-B intermolecular interactions are weaker than the A-A and B-B interactions.)

Explanation: Detailed explanation will be updated shortly.

Mock Test 09 Performance Solutions