Chemistry
An atom of an element has two electrons in the M shell. What is the
(a) atomic number
(b) number of protons in this element?
Atomic Structure
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Answer
(a) Number of electrons in the M shell = 2. So, the electrons in the K and L shells = 2 and 8
Hence, atomic number = 2 + 8 + 2 = 12
(b) As number of protons = number of electrons = 12
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