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प्रश्न
A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.
What is the mass number of X?
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उत्तर
Given: Protons = 17
Neutrons = 20
Formula: Mass Number = Number of Protons + Number of Neutrons
= 17 + 20
= 37
So, the mass number of particle X is 37.
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