Video Transcript
How does an atom form an anion?
First, let’s remind ourselves what
an anion is. An anion is a negatively charged
ion. To form an anion, our atom, which
is neutral, needs to gain negative charge. It does this by gaining
electrons. Normally, our atom has the same
number of protons as it does electrons. This gives our atom an overall
neutral charge. If we add an extra electron to our
atom, we’re going to tip the balance of the charge.
Now that we have more negative
charges than positive charges, the overall charge on our atom is negative. An atom with a negative charge is
called an anion. Remember that if an ion has a
positive charge, it’s called a cation. So, how does an atom form an
anion? The answer is by gaining
electrons.