N: 106Answer:
72 protons, 106 neutrons, 72 electrons.
Explanation:
to solve this use this simple method: APEMAN.
A= atomic number, P= Protons, E= Electrons.
M= Mass, A= atomic number, N= neutrons.
1. APE (atomic number, protons, electrons) are the same. since Hf (Hafnium) atomic number is 72, Hf has 72 protonsand ele ctrons.
2. to get Neutrons it will be mass-atomic number= neutrons.(M-A=N)
Hf mass= 178. So, 178-72= 106 neutrons.
