Question

5. An atom contains 12 protons, 12
electrons and 12 neutrons. What is its
(i) atomic number and (ii) Mass number​

Answer 1

Atomic number is equal to the number of protons. Therefore, atomic number is 12

Mass number=12+12

24u

Answer 2

Answer:

Magnesium, in its elemental form, has 12 protons and 12 electrons. The neutrons are a different matter. Magesium's average atomic mass is 24.305 atomic mass units, but no magnesium atom has exactly this mass...

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