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प्रश्न
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?
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उत्तर
Number of electrons in the M shell = 2
So, the number of electrons in the K and L shells will be = 2, 8
Hence, atomic number = 2 + 8 + 2 = 12
Number of protons = 12
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