The nucleus of an atom contains which of the following particles?

• A. Only electrons
• B. Protons and electrons
• C. Neutrons and protons
• D. Only neutrons

Answer: (C)

The nucleus of an atom is composed of two types of subatomic particles: protons and neutrons. Protons carry a positive charge, while neutrons are neutral and do not carry any charge. Together, these particles make up the bulk of the atom's mass and are essential for determining the atomic number and overall identity of the element.

Electrons, on the other hand, are found outside the nucleus in what is known as the electron cloud. They are much lighter than protons and neutrons and have a negative charge, which is why they are excluded from the nucleus.

Therefore, the presence of protons and neutrons in the nucleus is fundamental to the structure and behavior of atoms, making this the correct understanding of atomic composition.