Sure. The nucleus of an atom contains protons and neutrons, while atoms contain all three subatomic particles: protons, neutrons, and electrons.

• Protons have a positive charge, while neutrons have no charge. Electrons have a negative charge.

• The number of protons in an atom’s nucleus is called the atomic number, and it determines the element’s identity. For example, all atoms with 6 protons in their nucleus are carbon atoms.

• The number of neutrons in an atom’s nucleus can vary, and this gives rise to different isotopes of the same element. For example, carbon has two common isotopes: carbon-12, which has 6 protons and 6 neutrons, and carbon-14, which has 6 protons and 8 neutrons.

• Electrons are arranged in shells around the nucleus. The first shell can hold up to 2 electrons, the second shell can hold up to 8 electrons, the third shell can hold up to 18 electrons, and so on. The number of electrons in an atom’s outer shell determines how the atom will react with other atoms.

The reason why a nucleus contains protons but not neutrons is because of the strong force. The strong force is a force that binds quarks together. Quarks are the fundamental particles that make up protons and neutrons. The strong force is very strong, but it only works over very short distances. This means that the strong force can only hold protons and neutrons together in the nucleus of an atom.

The reason why atoms contain both protons and neutrons is because of the electrical force. The electrical force is a force that pushes oppositely charged particles together and pulls like-charged particles apart. Protons are positively charged, and electrons are negatively charged. This means that the electrical force pulls protons and electrons together.

The strong force and the electrical force are the two main forces that hold atoms together. The strong force holds protons and neutrons together in the nucleus, and the electrical force holds protons and electrons together in the atom.

I hope this explanation is helpful.