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प्रश्न
The mass number of an element is 23 and it contains 11 electrons. What is the number of protons and neutrons in it? What is the atomic number of the element?
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उत्तर
Given:
Mass no. = 23
No. of electrons = 11,
No of protons = No. of electrons = 11
No. of neutrons = 23 – 11 = 12
Atomic number of the element = 11
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