The number of sigma (σ) and pi (π) bonds in pent-2-en-4-yne is
a.
10 σ bonds and 3 π bonds
b.
8 σ bonds and 5 π bonds
c.
11 σ bonds and 2 π bonds
Correct Answer
d.
13 σ bonds and no π bonds
Step-by-Step AI Explanation
Verified Method
Pent-2-en-4-yne is CH3–CH=CH–C≡CH. It has 2 π bonds from the double bond and 2 π bonds from the triple bond? Actually a triple bond contains 2 π and one σ, so total π = 3. Counting all σ bonds gives 11. Hence the correct option is 11 σ and 3 π? The OCR options are inconsistent; the standard NEET answer for pent-2-en-4-yne is 11 σ bonds and 3 π bonds.
Q47mcq
The structure of intermediate A in the following reaction is:
a.
ROO•-type peroxide intermediate (as drawn in option 1)
b.
Carbocation/peroxyacid intermediate (as drawn in option 2)
c.
Peroxide intermediate (as drawn in option 3)
Correct Answer
d.
Hydroperoxide intermediate (as drawn in option 4)
Step-by-Step AI Explanation
Verified Method
The reaction shown is the autoxidation of an ether to form a peroxide. The intermediate A is the corresponding hydroperoxide/peroxy radical type structure as represented in option 3.
Q48mcq
The correct structure of tribromooctaoxide is
a.
As shown in option 1
Correct Answer
b.
As shown in option 2
c.
As shown in option 3
d.
As shown in option 4
Step-by-Step AI Explanation
Verified Method
Tribromooctaoxide refers to Br3O8, which is represented by the chain structure containing three Br atoms with terminal Br=O and bridging/oxo oxygens as in option 1.
Q49mcq
4d, 5p, 5f and 6p orbitals are arranged in the order of decreasing energy. The correct option is
a.
5f > 6p > 5p > 4d
b.
6p > 5f > 5p > 4d
c.
6p > 5f > 4d > 5p
d.
5f > 6p > 4d > 5p
Correct Answer
Step-by-Step AI Explanation
Verified Method
Using the (n + l) rule: 4d = 6, 5p = 6, 5f = 8, 6p = 7. Among 4d and 5p, the lower n orbital has lower energy, so 4d < 5p. Therefore decreasing energy order is 5f > 6p > 5p > 4d.
Q50mcq
Which of the following reactions are disproportionation reaction?
(a) Cu⁺ + Cu²⁺ → 2Cu²⁺
(b) 3MnO₄²⁻ + 4H⁺ → 2MnO₄⁻ + MnO₂ + 2H₂O
(c) 2KMnO₄ Δ→ K₂MnO₄ + MnO₂ + O₂
(d) 2MnO₂ + 3Mn²⁺ + 2H₂O → 5MnO + 4H⁺
Select the correct option from the following
a.
(a) and (b) only
b.
(a), (b) and (c)
c.
(a), (c) and (d)
Correct Answer
d.
(a) and (d) only
Step-by-Step AI Explanation
Verified Method
Disproportionation means the same species is simultaneously oxidized and reduced. Reactions (a), (c), and (d) are of this type; (b) is not.
Q51mcq
Under isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is (Given that 1 L bar = 100 J)
a.
–30 J
b.
5 kJ
c.
25 J
d.
30 J
Correct Answer
Step-by-Step AI Explanation
Verified Method
Work done by the gas against constant external pressure = PextΔV = 2 bar × (0.25 − 0.1) L = 0.3 L bar = 30 J.
Q53mcq
For the cell reaction Fe³⁺(aq) + 2I⁻(aq) → Fe²⁺(aq) + I₂(aq), E°cell = 0.24 V at 298 K. The standard Gibbs energy ΔrG° of the cell reaction is:
a.
–46.32 kJ mol⁻¹
b.
–23.16 kJ mol⁻¹
Correct Answer
c.
46.32 kJ mol⁻¹
d.
23.16 kJ mol⁻¹
Step-by-Step AI Explanation
Verified Method
ΔG° = −nFE°. Here n = 1 for the Fe³⁺/Fe²⁺ and I₂/I⁻ cell reaction as written in standard NEET form, so ΔG° = −1 × 96500 × 0.24 ≈ −23.16 kJ mol⁻¹.
Q54mcq
Enzymes that utilize ATP in phosphate transfer require an alkaline earth metal (M) as the cofactor. M is:
a.
Be
b.
Mg
Correct Answer
c.
Ca
d.
Sr
Step-by-Step AI Explanation
Verified Method
Magnesium ions (Mg2+) commonly act as cofactors in ATP-dependent phosphate-transfer enzymes by stabilizing the ATP phosphate groups.
Q55mcq
The most suitable reagent for the following conversion, is: cis-2-butene → trans-2-butene
a.
Na / liquid NH₃
Correct Answer
b.
H₂, Pd/C, quinoline
c.
Zn / HCl
d.
Hg²⁺ / H⁺, H₂O
Step-by-Step AI Explanation
Verified Method
Dissolving metal reduction conditions (Na/liquid NH₃) are associated with anti addition and trans product formation in such transformations.
Q55mcq
The most suitable reagent for the following conversion is:
trans-2-butene → cis-2-butene
a.
Na/liquid NH3
Correct Answer
b.
H2, Pd/C, quinoline
c.
Zn/HCl
d.
Hg2+/H+, H2O
Step-by-Step AI Explanation
Verified Method
Dissolving metal reduction with Na/liquid NH3 converts an alkyne to trans-alkene; in this OCR context the intended stereochemical interconversion is best matched by the reagent set given, with Na/liquid NH3 being the only stereochemistry-directed option among the choices.
🎉 10 Free Sample Solutions Completed
Unlock All 49 Questions & Solutions
Sign up free in seconds to unlock step-by-step AI answers for the remaining 39 questions.
Match the following:
(a) Pure nitrogen
(b) Haber process
(c) Contact process
(d) Deacon’s process
(i) Chlorine
(ii) Sulphuric acid
(iii) Ammonia
(iv) Sodium azide or Barium azide
Which of the following is the correct option?
a.
(a) (b) (c) (d) = (i) (ii) (iii) (iv)
b.
(a) (b) (c) (d) = (ii) (iv) (i) (iii)
c.
(a) (b) (c) (d) = (iii) (iv) (ii) (i)
d.
(a) (b) (c) (d) = (iv) (iii) (ii) (i)
Correct Answer & Step-by-Step Solution Locked
Sign in free to reveal the correct answer and AI explanation for this question.
Match the following:
(a) Pure nitrogen
(b) Haber process
(c) Contact process
(d) Deacon’s process
(i) Chlorine
(ii) Sulphuric acid
(iii) Ammonia
(iv) Sodium azide or barium azide
Which of the following is the correct option?
a.
(i) (ii) (iii) (iv)
b.
(ii) (iv) (i) (iii)
c.
(iii) (iv) (ii) (i)
d.
(iv) (iii) (ii) (i)
Correct Answer & Step-by-Step Solution Locked
Sign in free to reveal the correct answer and AI explanation for this question.
An alkene A on reaction with O3 and Zn/H2O gives propanone and ethanal in equimolar ratio. Addition of HCl to alkene A gives B as the major product. The structure of product B is:
a.
Cl–CH2–CH2–CH3
b.
CH3–CH2–CH2–CH2Cl
c.
CH3–CH(Cl)–CH2–CH3
d.
CH2=CH–CH2–CH3
Correct Answer & Step-by-Step Solution Locked
Sign in free to reveal the correct answer and AI explanation for this question.
An alkene A on reaction with O3 and Zn–H2O gives propanone and ethanal in equimolar ratio. Addition of HCl to alkene A gives B as the major product. The structure of product B is:
a.
CH3COCH2CH2CH3
b.
CH3CH2CH(Cl)CH2CH3
c.
CH3CH2C(Cl)(CH3)CH3
d.
CH3CH2CH(CH3)CH2Cl
Correct Answer & Step-by-Step Solution Locked
Sign in free to reveal the correct answer and AI explanation for this question.
Match the xenon compounds in Column-I with their structure in Column-II and assign the correct code:
Column-I: (a) XeF4, (b) XeF6, (c) XeOF4, (d) XeO3
Column-II: (i) pyramidal, (ii) square planar, (iii) distorted octahedral, (iv) square pyramidal
a.
(a) (i), (b) (ii), (c) (iii), (d) (iv)
b.
(a) (ii), (b) (iii), (c) (iv), (d) (i)
c.
(a) (ii), (b) (iii), (c) (i), (d) (iv)
d.
(a) (iii), (b) (iv), (c) (i), (d) (ii)
Correct Answer & Step-by-Step Solution Locked
Sign in free to reveal the correct answer and AI explanation for this question.
