What are isotopes?
Atoms of the same element with different numbers of neutrons.
AQA GCSE Combined Science: Trilogy (8464) — Physics — Higher · 6.4.1.2
Revise AQA GCSE Combined Science: Trilogy (8464) — Physics — Higher specification point 6.4.1.2, Mass number, atomic number and isotopes, with free active-recall flashcards. Flip through the set or review every question and answer below.
1 / 8
What are isotopes?
Atoms of the same element with different numbers of neutrons.
What do isotopes of an element have in common in terms of protons and atomic number?
They have the same number of protons and therefore the same atomic number.
What do different neutron numbers mean for isotopes’ mass numbers and masses?
Isotopes have different mass numbers and do not all have exactly the same mass.
What is the mass number of an atom?
The total number of protons and neutrons in its nucleus.
Why do protons and neutrons account for nearly all of an atom’s mass?
They are the heavy particles in the nucleus.
What is the atomic number of an atom?
The number of protons in its nucleus.
What does an atom’s atomic number identify?
Its element.
Where are the mass number and atomic number placed in nuclide notation?
The mass number is at the top left of the chemical symbol; the atomic number is at the bottom left.