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NEET2007ChemistrySome Basic Concepts of ChemistryActual

An element, X has the following isotopic composition: ²⁰⁰ X : 90 % ¹⁹⁹ X : 8.0 ²⁰² X : 2.0 % The weighted average atomic mass of the naturally-occurring element X is closest to

Options

  1. A201 amu
  2. B202 amu
  3. C199 amu
  4. D200 amu

Correct answer

D. 200 amu

Step-by-step solution

Average isotopic mass of aligned X & = 200 90+199+8+202 2 90+8+2 & = 18000+1892+404 100 & = 19996 100 =199.96 amu . aligned

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