The atom probably has 8 neutrons in the nucleus.
Atomic number (Z) is total number of protons and mass number (A) is total number of protons and neutrons in a nucleus.
N(p⁺) = Z = 7; number of protons in the atom
A = N(p⁺) + N(n°)
N(n°) = A - N(p⁺)
N(n°) = 15 - 7
N(n°) = 8; number of neutrons in the atom
N(e-) = N(p⁺) = 7; number of electrons in the atom
Neutron (symbol: n°) is a subatomic particle with no net electric charge.
Protons and neutrons are found in nucleus of an atom (atomic nuclei).
More about neutron: brainly.com/question/15120322
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