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Question 48

A learner adds electrons when calculating mass number. What is the correction?

  1. Count electrons but omit neutrons.
  2. Count only protons and neutrons.Correct answer
  3. Count every particle equally.
  4. Count electrons and neutrons only.

Explanation

Mass number includes the protons and neutrons in the nucleus and excludes electrons. Counting every atomic particle would change the defined quantity and incorrectly add very low-mass external particles.

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Question 48: A learner adds electrons when calculating mass number. What… · The Periodic Table and Elements · Questena