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Question 1361
StructuredStandard5 marks
CBSE Class 11 Chemistry · Chemical Bonding and Molecular Structure · Valence-bond and molecular-orbital theories

Compare O₂, O₂⁺, O₂⁻ and O₂²⁻ for

(a)
stability
(b)
magnetic behaviour.
Question 1362
McqStandard2 marks
CBSE Class 11 Chemistry · Classification of Elements and Periodicity in Properties · Atomic and ionic size

What chiefly determines the relative sizes of isoelectronic F⁻, Ne and Na⁺?

Question 1363
StructuredStandard3 marks
CBSE Class 11 Chemistry · Structure of Atom · Subatomic particles and atomic symbols

Two hundred million carbon atoms placed side by side extend \(2.4\,\mathrm{cm}\). Calculate the radius of one carbon atom.

Question 1364
StructuredStandard4 marks
CBSE Class 11 Chemistry · Some Basic Concepts of Chemistry · Stoichiometry and limiting reagents

Laboratory chlorine is made by 4HCl + MnO₂ → 2H₂O + MnCl₂ + Cl₂. Calculate the mass of HCl that reacts with \(5.0\,\mathrm{g}\) MnO₂.

Question 1365
StructuredStandard5 marks
CBSE Class 11 Mathematics · Limits and Derivatives · Derivatives from first principles

Differentiate from first principles: (i) x³−27(ii) (x−1)(x−2)(iii) 1/x²(iv) (x+1)/(x−1).

Question 1366
StructuredStandard3 marks
CBSE Class 11 Mathematics · Permutations and Combinations · Permutations

How many six-digit numbers using 0,1,3,5,7,9 exactly once are divisible by 10?

Question 1367
StructuredStandard3 marks
CBSE Class 11 Mathematics · Relations and Functions · Functions and their graphs

Let \(A=\{9,10,11,12,13\}\) and \(f(n)\) be the greatest prime factor of \(n\). Find the range.

Question 1368
StructuredStandard5 marks
CBSE Class 11 Mathematics · Sets · Complement and set identities

For \(U=\{1,2,\ldots,9\}\), \(A=\{2,4,6,8\}\), \(B=\{2,3,5,7\}\), verify both De Morgan laws.

Question 1369
NumericalStandard4 marks
CBSE Class 10 Science · Electricity · Series and parallel circuits

Two 24 Ω coils operate at 220 V separately, in series or in parallel. Find current in each arrangement.

Question 1370
StructuredStandard5 marks
CBSE Class 11 Mathematics · Probability · Algebra of events

Form four-digit numbers above 5000 from 0,1,3,5,7. Find the probability of divisibility by 5 (i) with repetition(ii) without repetition.