2.1.1 (b) Sub-atomic particles & Mass/Atomic Numbers

What does this mean?

There is little to learn here that would not have been covered in any GCSE course.

You should recall the properties of the 3 basic subatomic particles.

There are many other sub-atomic particles but those are in the realm of Physics - and therefore of no interest to anyone.

For the purposes of Chemistry, the relative mass of an electron is generally treated as zero.

With any luck you'll recall the location of the Atomic and Mass numbers.

If not there is a key on the Periodic Table in the exam but if you need to refer to it perhaps you should consider swapping to Media Studies while there's still time.

Physicists refer to the Atomic number as the Proton number to remind them that this is what it counts.

But since atoms are neutral - any atom with 9 protons in its nucleus would also have to have 9 electrons in its shells.

Though this isn't true for ions - which have charges.

Physicists refer to the Mass number as the Nucleon number because it makes them feel clever.

This is because the Mass number counts the particles which have significant masses (protons and neutrons) and these are found in the nucleus (hence nucleon).

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