Question 61:

Assertion (A): The first ionisation enthalpy decreases across a period.
Reason (R): The increasing nuclear charge outweighs the shielding across the period.

1. Both A and R are true and R is the correct explanation of A
2. A is true but R is false
3. A is false but R is true
4. Both A and R are true but R is NOT the correct explanation of A

Question 62:

Match List I with List II

LIST I (Substances) | LIST II (Element Present)
A. Ziegler catalyst | I. Rhodium
B. Blood Pigment | II. Cobalt
C. Wilkinson catalyst | III. Iron
D. Vitamin B12 | IV. Titanium

Correct Answer: (4) A-IV, B-III, C-I, D-II

Question 63:

In the chromyl chloride test for Cl⁻, a yellow solution is obtained. Acidifying and adding amyl alcohol + 10% H₂O₂ turns organic layer blue, showing chromium pentoxide (CrO₅). The chromium oxidation state is:

1. +6
2. +5
3. +4
4. +3

Question 64:

The difference in energy between the actual structure and the lowest energy resonance structure is called:

1. electromeric energy
2. resonance energy
3. ionization energy
4. hyperconjugation energy

Question 65:

Two statements on Group 14 elements:
Statement I: Electronegativity from Si to Pb decreases gradually.
Statement II: Group 14 has nonmetallic, metallic, and metalloid members.

1. Statement I false, Statement II true
2. Statement I true, Statement II false
3. Both I & II true
4. Both I & II false

Question 66:

Correct set of four quantum numbers for the valence electron of rubidium (Z=37):

1. 5,0,0,+1/2
2. 5,0,1,+1/2
3. 5,1,0,+1/2
4. 5,1,1,+1/2

Question 67:

The major product (P) in a reaction: options mention an alkene side chain + conc HBr, leading to bromo-substituted product, is:

1. Structure 1
2. Structure 2
3. Structure 3
4. Structure 4

Question 68:

The arenium ion not involved in bromination of aniline is:

1. Structure 1
2. Structure 2
3. Structure 3
4. Structure 4

Question 69:

Blood red color (thiocyanate test) from sodium fusion extract + FeSO₄ + acid => indicates presence of:

1. Br
2. N
3. N & S
4. S

Question 70:

Aryl halides cannot be prepared by simply replacing hydroxyl group of phenol by halogen with halogen acid. The statement claims halogen acids react violently with phenols. Which is correct?

1. Both A & R true but R not correct explanation
2. A false, R true
3. A true, R false
4. Both A & R true & R correct explanation

Question 71:

Identify product A & product B in a multistep reaction:

1. A from electrophilic substitution, B from radical substitution
2. A from nucleophilic addition, B from electrophilic addition
3. A from free radical addition, B from electrophilic substitution
4. A via free radical mechanism, B via electrophilic addition

Question 72:

Which is the incorrect pair?

1. Fluorspar = BF₃
2. Cryolite = Na₃AlF₆
3. Fluoroapatite = 3Ca₃(PO₄)₂·CaF₂
4. Carnallite = KCl·MgCl₂·6H₂O

Question 73:

Interaction between a pi bond & a lone pair on an adjacent atom is responsible for:

1. Hyperconjugation
2. Inductive effect
3. Electromeric effect
4. Resonance effect

Question 74:

KMnO₄ heating at 513 K forms O₂ plus what byproducts?

1. MnO₂ & K₂O₂
2. K₂MnO₄ & Mn
3. Mn & KO₂
4. K₂MnO₄ & MnO₂

Question 75:

In which metal carbonyl does CO bridge between metals?

1. [Co₂(CO)₈]
2. [Mn₂(CO)₁₀]
3. [Os₃(CO)₁₂]
4. [Ru₃(CO)₁₂]

Question 76:

Amino acids released by hydrolysis of proteins are:

1. β-amino acids
2. α-amino acids
3. δ-amino acids
4. γ-amino acids

Question 77:

In a multistep reaction: final product A formed is…

1. Product is an alkane (option 1)
2. …
3. …
4. …

Question 78:

Which is not correct about ΔG for a reaction?

1. ΔG negative => spontaneous
2. ΔG positive => spontaneous
3. ΔG=0 => equilibrium
4. ΔG positive => non-spontaneous

Question 79:

Chlorine disproportionation in alkaline medium:
a Cl₂(g)+ b OH⁻(aq)-> c ClO⁻(aq)+ d Cl⁻(aq)+ e H₂O(l). The coefficients a,b,c,d => ?

1. 1,2,1,1
2. 2,2,1,3
3. 3,4,4,2
4. 2,4,1,3

Question 80:

In alkaline medium, permanganate (MnO₄⁻) oxidizes I⁻ to… ?

1. IO₄⁻
2. IO⁻
3. I₂
4. IO₃⁻

Question 81:

Number of compounds with exactly one lone pair on the central atom among: O₃, H₂O, SF₄, ClF₃, NH₃, BrF₅, XeF₄

Question 82:

Mass of zinc produced by electrolysis of ZnSO₄ with 0.015 A for 15 min => ?×10⁻⁴ g

Question 83:

A reaction in three steps (same T) overall rate K=K₁K₂/K₃. If Eₐ₁=40, Eₐ₂=50, Eₐ₃=60 kJ/mol => overall Eₐ=?

Question 84:

For N₂O₄(g) ⇌ 2NO₂(g), Kₚ=0.492 atm at 300 K. Then Kc=? (R=0.082 L atm mol⁻¹ K⁻¹)

Question 85:

H₂SO₄ solution: 31.4% by mass, density=1.25 g/mL => approximate molarity=?

Question 86:

Osmotic pressure=7×10⁵ Pa at 273 K => at 283 K=? ×10⁴ N/m²

Question 87:

Number of compounds containing sulfur among Furan, Thiophene, Pyridine, Pyrrole, Cysteine, Tyrosine?

Question 88:

Number of species paramagnetic & bond order=1 among H₂, He₂⁺, O₂⁺, N₂⁻, O₂²⁻, F₂, Ne₂⁺, B₂ is:

Question 89:

From the list: Benzaldehyde, Acetaldehyde, Acetone, Acetophenone, Methanal, 4-nitrobenzaldehyde, Cyclohexane carbaldehyde, how many give positive Fehling’s test?

Question 90:

Reaction: CH₃-CH=CH-CH₃ → (i)O₃, (ii)Zn/H₂O → 2CH₃-CHO. The total oxygen atoms per molecule of product is ?