What is a particle with an unequal number of protons and electrons?

Atoms are composed of a dense, massive nucleus containing charged particles, #"protons"#, and uncharged particles, #"neutrons"#. At nuclear ranges, these particles engage in the strong nuclear force; an attractive force, which at nuclear ranges is STRONGER than the electrostatic force of repulsion that operates between like-charged particles.

Around the positively-charged nucleus, electrons, particles of NEGLIGIBLE mass, but unit NEGATIVE, electronic charge, whizz about. In the neutral atom, NECESSARILY there are equal number of protons, massive, charged nuclear particles, and electrons, mass-less, extra-nuclear particles of OPPOSITE charge to the nuclear charge.

Now the identity of the element is defined by the number of nuclear charges...i.e. #Z_"the atomic number"="number of protons"#. Where these is an equal number of electrons to #Z# the element is NECESSARILY electrically neutral. An excess OR deficiency of electrons results in an anion or cation given #Z#.

Metal are reducing, electron-rich materials, and typically LOSE electrons to form cations:

#M(g) +Delta rarrM^(+)(g) + e^(-)#

On the other hand, non-metals are oxidizing, electron-poor materials, and typically GAIN electrons to form anions:

#1/2O_2(g) + 2e^(-) rarr O^(2-)#

#1/2F_2(g) + e^(-) rarr F^(-)#

Capisce?