This element can be produced via fusion of two carbon atoms at 600 megakelvins in a star  with at least three solar masses, or in a Downs Cell or by electrolysis in the Castner process.  
This element can be produced via fusion of two carbon atoms at 600 megakelvins in a star  with at least three solar masses, or in a Downs Cell or by electrolysis in the Castner process.  Vapor lamps made of this element are used for street lighting and give off a distinctive yellow  light, and it was discovered through electrolysis by Humphry Davy. This soft, silvery metal is  exchanged with potassium in a namesake pump. For 10 points, identify this element with atomic  number 11, which forms a common condiment with chloride.
This element can be produced via fusion of two carbon atoms at 600 megakelvins in a star  with at least three solar masses, or in a Downs Cell or by electrolysis in the Castner process.  
sodium or Na