Q72.If Cr ≡25Cr and C0 + 5 ∙C1 + 9 ∙C2 + … + (101) ∙C25 = 225 ∙k, then k is equal to ____________.
What This Question Tests
This question tests the ability to evaluate a complex summation involving binomial coefficients multiplied by an arithmetic progression, requiring the use of known identities for such sums (or differentiation of binomial expansion).
Concepts Tested
Formulas Used
Σ C_r = 2^n
Σ r C_r = n 2^(n-1)
Σ r^2 C_r = n(n+1)2^(n-2)
📚 NCERT Sections This Tests
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
5.17 — What Is Spectrochemical Series? Explain The Difference Between A Weak
Chemistry Class 11 · Chapter 5
5.17 What is spectrochemical series? Explain the difference between a weak field ligand and a strong field ligand.
5.18 — What Is Crystal Field Splitting Energy? How Does The Magnitude Of Do Decide
Chemistry Class 11 · Chapter 5
5.18 What is crystal field splitting energy? How does the magnitude of Do decide the actual configuration of d orbitals in a coordination entity?
📋 Question Details
- Chapter
- Binomial Theorem
- Topic
- Summation involving binomial coefficients
- Year
- 2020
- Shift
- 09 Jan Shift 2
- Q Number
- Q72
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 8: Binomial Theorem
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