Chocolate: difference between “Cocoa Mass” and “Cacao”?

There isn't much diary products in my country. So cheese, double/heavy cream, baking chocolate etc are hard to find.

Some shops that specialize in baking sells this relatively expensive "72% cocoa mass" chocolate. While the supermarket has cheaper, baking chocolate that has "100% cacao". I don't remember the brand but it is something like this one.

How do i compare "100% cacao" to "72% cocoa mass"? Are they the same, and hence the 100% one has higher cocoa/cacao content?