Properties🧐
Elements consist of one type of atom only.
Quite a lot of everyday substances are elements:
Copper, Aluminium, Iron, Oxygen, Nitrogen.
Each element has a different number of protons. It's the number of protons in an atom that decides what element it is. For example, any atom of the element helium will have 2 protons - any atom with 2 protons will be a helium atom.
Atomic Number & Mass Number
Each element has an atomic number and a mass number.
MASS NUMBER (TOP NUMBER) - this tells you the total number of protons and neutrons in the atom.
ATOMIC NUMBER (BOTTOM NUMBER) - this tells you the number of protons in an atom (and so the number of electrons too).
Neutron Number
In I/GCSE Chemistry, you will be asked to find the number of neutrons in an atom...
To do this, you subtract the atomic number from the mass number (bottom number from the top number).
E.g. there are 8 neutrons in an oxygen nucleus because 16-8=8.
Reference: https://lh3.googleusercontent.com/proxy/OpSkYQiE3TIZdw8e-kd7BPB4iFMNfwQNy3fee1ILyWQXouY9EexRrjyPrO6qshk7AftzKFzAqiMi8EqKzFsPNZZMmxpXkpiUnJNjj6DAIWR-SiiVWTgUewqABKs
https://www.chemistrygcse.co.uk/1%20-%20Core%20Chemistry/Atoms/protonsneutronselectrons.html
Drafted by Catrina (Chemistry)