The atomic masses of three elements A, B and C having similar chemical properties are 7, 23 and 39, respectively - Science and Technology 1

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The atomic masses of three elements A, B and C having similar chemical properties are 7, 23 and 39, respectively.

  1. Calculate the average atomic mass of elements A and C.
  2. Compare the average atomic mass with atomic mass of B.
  3. What could the elements A, B and C be?
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Solution

(a) The average atomic mass of elements A and C = `(7+39)/2=46/2=23`

(b) The average atomic mass of elements A and C is equal to the atomic mass of element B.

(c) A is lithium, B is sodium and C is potassium.

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2012-2013 (March)

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