True. These ions are of a 2- charge. Oxygen is an example. It will form a 2- charge if ionize.
Most rocks that we encounter in our normal everyday lives are sedimentary rocks. Sedimentary rocks are rocks that have been worn down gradually over long periods of time. Because it takes very long periods of time (couple decades) for these rocks to change, it often seems as if they don't change at all, when in reality the change is too small for us to realize it!
A cation is a positively charged ion.
An anion is a negatively charged ion.
If it's neutral, it's just an ion.
This means a release of free energy from the system corresponds to a negative change in free energy, but to a positive change for the surroundings.
