Which of the following best explains why a neutral magnesium atom (atomic number 12)…
CHEMISTRY · Single correct · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
Which of the following best explains why a neutral magnesium atom (atomic number 12) becomes a particle with a +2 charge after two of its electrons are removed?
(a) Ionisation adds two protons to the nucleus while the electron count stays the same, so the net positive charge increases by +2.
(b) Removing two electrons lowers the atomic number from 12 to 10; the resulting neon ion naturally carries a +2 charge.
(c) Removing two negatively charged electrons leaves the 12 positive protons unbalanced by just 10 electrons, producing a net charge of +2.
(d) The nucleus absorbs two additional neutrons, and some students think this raises the positive charge by two, yielding a +2 ion.