1. The fuel for the system was of monomethylhydrazine and nitrogen tetroxide . 2. The osmium tetroxide molecule is tetrahedral and therefore non-polar. 3. Oxidation with ammonium persulfate and dilute caustic soda gives bismuth tetroxide . 4. ABC suggested that osmium tetroxide would cause victims to choke to death. 5. All the lighter members have known or hypothetical tetroxides , MO 4. 6. The most common compound exhibiting the + 8 oxidation state is osmium tetroxide . 7. Osmium powder has the characteristic smell of osmium tetroxide . 8. The cells are black as a result of the effects of osmium tetroxide . 9. This was reportedly changed to a hypergolic nitrogen tetroxide / hydrazine propulsion system. 10. Pentaborane was also investigated to be used as a bipropellant with nitrogen tetroxide .