Chemistry different mass numbers are known as isotopes. For example, all atoms with 6 protons in their nuclei are atoms of the chemical element carbon, but atoms of carbon may have mass numbers of 12 or 13. The standard presentation of the chemical elements is in the periodic table, which orders elements by atomic number. The periodic table is arranged in groups, or columns, and periods, or rows. The periodic table is useful in identifying periodic trends. A "compound" is a pure chemical substance composed of more than one element. The properties of a compound bear little similarity to those of
Atomic spacing frequency through the material, and using the laws of diffraction to determine its atomic spacing. Bond length can be determined between different elements in molecules by using the atomic radii of the atom. Carbon bonds with itself to form two covalent network solids. Diamond's C-C bond has a distance of 0.142 nm away from each carbon, while graphite's C-C bond has a distance of 0.341 nm away from each carbon. Although both bonds are between the same pair of elements they can still have different bond length. Atomic spacing Atomic spacing refers to the distance between the nuclei of atoms