If we take the wolf as a species, then we can easily find its place and evolutionary path through this cladogram of chordates. The wolf is a vertebrate, so we start from vertebrae. It is an animal that has jaws and paired appendages. Continuing further up the cladogram we reach the development of lungs, and the wolfs have lungs for breathing. Then we come to the development of four limbs, and the wolfs have four limbs. Next comes the endothermy, meaning that the animal is able to regulate its own body temperature, thus it is warmblooded, and the wolfs are warmblooded animals. As last we come to the mammals, and the wolfs are part of the mammals, so we can classify them in that branch of the chordate cladogram.
The chemical formula for water is H2O which means that every molecule of water has 2 atoms of hydrogen (H) and one atom of oxygen (O). Here comes the key part. From the Periodic Table of Elements, one sees that one molecule of oxygen atoms weigh 16 grams.
I apologize if this is not what you meant. If you have further questions just tell me.
