Magnesium oxide Magnesium oxide Magnesium oxide (MgO), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of and consists of a lattice of Mg ions and O ions held together by ionic bonding. Magnesium hydroxide forms in the presence of water (MgO + HO → Mg(OH)), but it can be reversed by heating it to separate moisture. Magnesium oxide was historically known as magnesia alba (literally, the white mineral from magnesia – other sources give magnesia alba as MgCO), to differentiate it from "magnesia
I Should Have Known Better It was not released as a single at that time. In 1976, it was released as a B-side to "Yesterday". In the US, "I Should Have Known Better" was released on 13 July 1964 as the B-side to "A Hard Day's Night" and reached number 53 in the "Billboard" Hot 100, and number 43 on the "Cash Box" chart. As part of the film contract, United Artists acquired album rights for the American market. The company released a soundtrack album on 26 June 1964 with eight Beatles songs and four instrumentals. "I Should Have Known Better" was performed in the