Caesium oxide It is a good electron emitter; however, its high vapor pressure limits its usefulness. Elemental magnesium reduces caesium oxide to elemental caesium, forming magnesium oxide as a side-product: CsO is hygroscopic, forming the corrosive CsOH on contact with water. Caesium oxide Caesium oxide (IUPAC name) or cesium oxide describes inorganic compounds composed of caesium and oxygen. The following binary (containing only Cs and O) oxides of caesium are known: CsO, CsO, CsO, and CsO. Both the oxide and suboxides are brightly coloured. The species CsO forms yellow-orange hexagonal crystals. Caesium oxide is used in photocathodes to detect infrared signals in
U Should've Known Better song entered the "Billboard" Hot 100 chart, where it debuted at number 67 in the week of June 6, 2004, the second-highest debut of the week. "U Should've Known Better" remained twenty weeks on the chart, reaching its peak position of number 19 in its ninth week. It marked the second single from "After the Storm" to reach the top twenty on the Hot 100chart and, as the album's final single, would remain its second highest-charting offering behind leading single "So Gone." Although never released on a CD single or CD maxi single format, "U Should've Known Better" was also