What is the sum of protons and neutrons?

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Atoms are the smallest fragments of matter that retain their chemical identity. Atoms contain a number of particles, including protons, neutrons and electrons. Among these, protons are positively charged, while electrons are negatively charged and neutrons are neutrally charged. The protons and neutrons exist within the nucleus, while electrons are...

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Atoms are the smallest fragments of matter that retain their chemical identity. Atoms contain a number of particles, including protons, neutrons and electrons. Among these, protons are positively charged, while electrons are negatively charged and neutrons are neutrally charged. The protons and neutrons exist within the nucleus, while electrons are located outside it. 

Each element is characterized by two terms: atomic number and mass number. The atomic number is the same as the number of protons in the nucleus. Mass number, on the other hand, is the sum total of protons and neutrons of an atom.

To determine the number of protons and neutrons in the atoms of a given element, we need to know the atomic number and mass number of the element. Using that information, we can find the number of protons and neutrons as:

number of protons = atomic number

number of neutrons = mass number - number of protons

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