Six astronauts are still on the space station as part of a planned year-long stay in space, the longest tour of duty in the station's 15-year history.
The molecular formula of citric acid is C 6 H 8 O 7. The chemical formula for citric acid is best shown by a diagram of its complete structural formula. This shows how the atoms are arranged in the molecule. Citric acid has three carboxyl or-COOH groups and is triprotic in nature.
Sulfuric acid in its pure form is a colorless viscous liquid commonly called oil of vitriol. The chemical formula for sulfuric acid is H 2 SO 4 and it is commercially available as a 96-98% solution or 18M H 2 SO 4. Concentrated sulfuric acid is covalent in nature as the acid is unionized. The atoms in the molecule are covalently bonded to one another. In this form sulfuric acid can be transported in stainless steel tankers. If concentrated sulfuric acid is added to water the reaction is extremely exothermic due to formation of hydrogen ions.