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NTA Abhyas JEE Main2020ChemistryClassification of Elements and Periodicity in PropertiesPractice

The atomic masses of L i and K are 7 and 39, respectively. According to law of triads the atomic mass of N a will be

Options

  1. A23
  2. B32
  3. C46
  4. D64

Correct answer

A. 23

Step-by-step solution

Atomic mass of middle element of triad is equal to average of masses of terminal elements. L i Na K 7 23 39 7 + 39 2 = 23

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