Mammoth Memory

Mass number

The mass number is the number of protons plus the number of neutrons in the atom. It is always the biggest number and is roughly double the atomic number.

The mass number is the protons plus neutrons, and is roughly double the atomic number
The mass number is represented by a bull mastiff eating a bowl of peas (protons) and newts (neutrons). (I.e. all the live yummy bits, not electronic robots (electrons), because who wants to eat an electronic robot!) 
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