Period 1 element lithium and fluorine (appearing twice), or left floating above the other elements and not assigned to any group in the periodic table. Helium is almost always placed above neon (which is in the p-block) in the periodic table as a noble gas, although it is occasionally placed above beryllium due to their similar electron configuration. Hydrogen (H) is the chemical element with atomic number 1. At standard temperature and pressure, hydrogen is a colorless, odorless, nonmetallic, tasteless, highly flammable diatomic gas with the molecular formula H. With an atomic mass of 1.00794 amu, hydrogen is the lightest element. Hydrogen is
Period 4 element people in the world suffer from zinc deficiency. However, too much zinc can cause copper deficiency. Zinc is often used in batteries, aptly named carbon-zinc batteries, and is important in many platings, as zinc is very corrosion resistant. Gallium (Ga) is an element in period 4, between zinc and germanium. Gallium is noteworthy because it has a melting point at about 303 kelvins, right around room temperature. For example, it will be solid on a typical spring day, but will be liquid on a hot summer day. Gallium is an important component in the alloy galinstan, along with tin. Gallium