Respuesta :
b.125 no of electrons=atomic no no of neutrons+no of electrons=mass no no of neutrons=mass no-no of electrons no of neutrons=210-85 no of neutrons= 125
- There are 125 neutrons contained in the atom
- Atomic number can be regarded as the number of electrons in that atom.
- Hence, atomic number = 85, and number of electrons is 85
- Mass number is the addition of number of electrons as well as number of neutrons. It can be calculated as
- Mass number = ( number of electrons) + ( number of Neutron)
- ( number of Neutron) = (Mass number ) - ( number of electrons)
Substitute the values
- ( number of Neutron) = ( 210 - 85)
= 125
Therefore, the correct option is B, which is 125 electrons
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