Introduction

Nuclear Chemistry : Introduction

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Atomic number: protons (and electrons if neutral)

Mass number: protons + neutrons (neutrons = mass number - atomic number)

Isotope - Atoms of the same element (with the same atomic number and number of protons) but with different masses (number of neutrons).

Symbols for isotopes:

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Isobars - Atoms with the same mass but different atomic numbers.

Isotones - Atoms with the same number of neutrons but different masses and atomic numbers.

The mass of an atom is measured in the atomic mass units (amu).

Mass of proton = 1.007276 amu 1 amu

Mass of neutron = 1.008665 amu 1 amu

Atomic mass - The weighted average of all isotopes based on each isotope's abundance.