6.4.1.2 Atomic Number, Mass Number and Isotopes — AQA Combined Science Trilogy 8464

Understand that atoms possess no overall electrical charge because the number of electrons equals the number of protons.
Define the atomic number as the number of protons in the nucleus, and recognize that all atoms of a specific element have the same atomic number.
Define the mass number as the total number of protons and neutrons in an atom's nucleus.
Interpret standard atomic representations and nuclear symbols.
Define isotopes as atoms of the same element that have different numbers of neutrons.
Explain how atoms become positive ions by losing one or more outer electrons.
Relate the differences between isotopes to variations in their conventional representations, identities, charges, and masses.

Understand that atoms possess no overall electrical charge because the number of electrons equals the number of protons.
Define the atomic number as the number of protons in the nucleus, and recognize that all atoms of a specific element have the same atomic number.
Define the mass number as the total number of protons and neutrons in an atom's nucleus.
Interpret standard atomic representations and nuclear symbols.
Define isotopes as atoms of the same element that have different numbers of neutrons.
Explain how atoms become positive ions by losing one or more outer electrons.
Relate the differences between isotopes to variations in their conventional representations, identities, charges, and masses.

Atomic Number, Mass Number and Isotopes