I found this at WikiPedia. It's pretty close. Magnesium Hydroxide is Milk of Magnesia. They show Magnesium Hydroxide from a magnesium salt: ----- The chemical formula of sodium hydroxide is NaOH. The chemical formula of magnesium hydroxide is Mg(OH)2.
Sodium carbonate has sodium, carbon and oxygen in it, and the molecular formula is NaCO. Sodium hydroxide is consists of the elements sodium, oxygen and hydrogen and it has the molecular formula NaOH. One of the common features of both these compounds are being alkali in aqueous medium.