The Student Room Group
an ion is an atom with more or less electrons makinf it positively or negatively charged. the reason they have included this is to confuse you a little, because it could be either the protons or electrons.

in this case you've got to subtract the number of protons from the atomic mas to give you the number of neutrons because its focusing on the mass and not the charge (as electrons have a very very tiny mass which is not really taken into account)
Reply 2
riggghhhhht the charge is really simple m8 thankyou i can finally rest cheers bud

Latest