Lithium be cut with a knife. When cut, it possesses a silvery-white color that quickly changes to gray as it oxidizes to lithium oxide. While it has one of the lowest melting points among all metals (180 °C), it has the highest melting and boiling points of the alkali metals. Lithium has a very low density (0.534 g/cm), comparable with pine wood. It is the least dense of all elements that are solids at room temperature; the next lightest solid element (potassium, at 0.862 g/cm) is more than 60% denser. Furthermore, apart from helium and hydrogen, it is less dense than
Standard day fuel to complete the flight to the destination, the pilot would plan an intermediate fuel stop, which would likely delay the final destination arrival time. In meteorology, departure from standard day conditions is what gives rise to all weather phenomena, including thunderstorms, fronts, clouds, even the heating and cooling of our planet. For Pilots: At sea level, Altimeter:29.92 in/Hg at The "standard day" model of the atmosphere is defined at sea level, with certain present conditions such as temperature and pressure. But other factors, such as humidity, further alter the nature of the atmosphere, and are also defined under standard