Question 42

In an atomic-number-and-mass table, which entry cannot be an atomic number?

8
17
12.6Correct answer
26

Explanation

An atomic number counts protons, so it must be a whole number and cannot be 12.6. A decimal displayed for an element is more likely a mass average, not a fractional proton count.

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Question 42: In an atomic-number-and-mass table, which entry cannot be… · The Periodic Table and Elements · Questena