Answer:
Cobalt is the twenty seventh element.
Step-by-step explanation:
It has 27 protons, so an atomic number of 27, and is the twenty seventh element. Before cobalt, from the first element, it is hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, calcium, scandium, titanium, vanadium, chromium, manganese, iron, cobalt.