Final answer:
The small, dense core of an atom is called the nucleus, which contains protons and neutrons. It is about 1/100,000 the overall size of an atom and makes up 99.97% of the atom's mass. The strong nuclear force keeps the protons and neutrons together in a stable existence.
Step-by-step explanation:
The small, dense core of an atom is called the nucleus. It is about 1/100,000 the overall size of an atom. The nucleus contains protons (positive charge) and neutrons (no charge), and it makes up 99.97% of the atom's mass. Despite the strong electromagnetic forces that resist the close congregation of positively charged protons, the strong nuclear force overpowers this objection and sticks the protons and neutrons together in a stable existence.
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