In this problem we want to determine the number of
protons, nuetrons, and electrons for this anionic compound
And so, let's write down what we know.  We have
two carbons, five hydrogens, one oxygen
We want the number of protons, and the nuetrons, and electrons
So atomic number for carbon is six. hydrogen's one
oxygen is eight.  So two times this because we have
two carbons, five times, and then one times this
Now, electrons, it's the same number in the nuetral
compound, and the nuetrons we can determine from
the periodic table.  Since the atomic mass of carbon
is 12, there's six nuetrons and of course
two carbons, so that's times two.  There are none
in hydrogen, and there are eight in oxygen.  So
again eight, and times one.  So we add the numbers
up.  And we'll end up with the numbers for the nuetral compound
However since the charge is -1 means we have
one more electron.  So we have 25 protons, 20 nuetrons
and 26 electrons in this anionic compound
