Living organisms use atoms from sugar molecules combined with other elements to form lipids and nucleic acids. Lipids are hydrophobic organic compounds composed of carbon and a high ratio of hydrogen to oxygen. Nucleic acids are an acidic polymer of nucleotides found or produced in the cell nucleus.
Chromium has the electron configuration [Ar]4s13d5 and exhibits oxidation numbers 2+, 3+, and 6+. When chromium loses two electrons, it forms the Cr2+ ion and has the configuration [Ar]3d4.
