- A proton has a positive 1 electric charge
- A neutron has a neutral 0 electric charge
- So, protons and neutrons together will be positive in electric charge

- Protons and neutrons together will be positive in electric charge
- The nucleus of an atom is made of protons and neutrons
- Hence, the nucleus of an atom is positve in electric charge

- The nucleus of an atom is positve in electric charge
- The nucleus is the center of an atom
- So, the positive charge is concentrated in the center of an atom

Therefore, the positive charge is concentrated in the center of an atom
In the atomic model that includes a nucleus, the positive charge is
- A proton has a positive 1 electric charge 
- A neutron has a neutral 0 electric charge 
- The nucleus of an atom is made of protons and neutrons 
- The nucleus is the center of an atom