C1 - Atomic Structure and the Periodic Table. - Coggle Diagram
C1 - Atomic Structure and the Periodic Table.
Atoms contain protons, neutrons and electron
Electrons have almost no mass.
They're negatively charged.
Move around the nucleus in electron shells (levels).
Almost the whole mass of the atom is in the nucleus.
It has a positive charge because of the protons.
The nucleus has radius of around 1 x 10-14m (that's around 1/10000 of the atomic radius).
It contains protons and neutrons.
It's in the middle of the atom.
Protons are heavy (compared to electrons) and positively charged.
Neutrons are heavy (compared to electrons) and neutral.
Electrons are tiny and negative charged.
Atomic number and Mass number describe an atom
The nuclear symbol of an tom tells you its atomic (proton) number and mass number.
Atomic number = number of protons
Mass number = number of protons + number of neutrons
Number of neutrons = mass number - atomic number
Atoms have no charge overall. They're neutral.
This is because they have the same number of protons as electrons. So, in an atom number of electrons = atomic number
The charge on the electrons is the same size as the charge on the protons, but opposite - so they cancel out.
In an ion, the number of protons doesn't equal the number of electrons. This means it has an overall charge for example an ion with a 2 - charge has two more electrons than protons.
In a positive ion: number of electrons = atomic number - charge
in a negative ion: number of electrons = atomic number - charge