Yes, both oxygen and copper are elements. An element is a pure substance that cannot be broken down into simpler substances by chemical means. Oxygen is a chemical element with the symbol O and atomic number 8. It is a colorless, odorless, tasteless diatomic gas with a slightly sweet odor. Copper is a chemical element with the symbol Cu and atomic number 29. It is a reddish-brown, malleable, ductile metal with high thermal and electrical conductivity.