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.
Formula and structure: The chemical formula of nitric acid is HNO3. Its molecular formula is written as NHO3 and its molar mass is 63.01 g/mol. The chemical structure of nitric acid is shown below, with its resonance forms: The HNO3 molecule is planar with the nitrogen attached to three oxygen atoms, one of which holds the proton.