Carbon Dioxide — properties & hazards overview
Sublimation point
−78.5 °C (1 atm)
Vapour density
1.98 g/L (0 °C) — 1.5× air
Water solubility
1.7 g/L (20 °C), forms H₂CO₃
Flammability
Non-flammable (inert)
Toxicity
Asphyxiant above ~4 vol%
Flammability
Non-flammable
Chronic risk
No chronic toxicity
Environmental
Greenhouse gas
| Property | Value / Note |
|---|---|
| Chemical formula | CO₂ |
| Molar mass | 44.01 g/mol |
| Physical state | Colourless, odourless gas |
| Solution chemistry | CO₂ + H₂O → H₂CO₃ → HCO₃⁻ → CO₃²⁻; absorption rises steeply above pH 9. |
| Occupational limits | Typically 5 000 ppm TWA / 15 000 ppm STEL — verify against local regulation. |
| Typical sources | Combustion, pyrolysis, fermentation, calcination and acid dosing of carbonate liquors. |
| Best analytical detection | NDIR — the reference method for CO₂ in flue gas: linear, robust and unaffected by water when the sample is conditioned. FTIR where CO₂ is measured alongside other species. |
*Values are indicative and may vary by source. For safety and design, always consult current SDS and regulations.