Copper is a transition element and metal in the periodic table of elements. Its atomic number is 29. The electronic configuration of copper is different than expected as it can have fully filled orbitals to be stable. Copper was the second element on earth that was discovered by the early man. It is a strong metal and is sometimes used as an alloy. Copper always forms ionic bonds and Metallic bonds. Copper is one of the least reactive elements in the reactivity series.