Calculator
Example data table
Use these sample cases to verify your setup.
| Method | Inputs | Output (example) |
|---|---|---|
| Mass → Moles | 44.0095 g CO2 | ≈ 1 mol |
| Moles → Mass | 2 mol CO2 | ≈ 88.019 g |
| ppm(v) → mg/m³ | 420 ppm, 25°C, 101.325 kPa | ≈ 770 mg/m³ |
| Fuel carbon → CO2 | 10 kg fuel, 86% carbon | ≈ 27.2 kg CO2 |
Formula used
- Moles from mass: n = m / M
- Mass from moles: m = n × M
- ppm(v) to mg/m³ (ideal gas): c = ppm × 10⁻⁶ × P/(R×T), then mg/m³ = c × M × 1000
- CO2 from fuel carbon: m(CO₂) = m(C) × M(CO₂)/M(C), where m(C)=m(fuel)×carbon%
How to use this calculator
- Select a method from the dropdown.
- Enter values with the correct units.
- Set rounding if you need fewer decimals.
- Press Calculate to display results above the form.
- Use Download buttons to export the latest result.
FAQs
1) What molar mass does the calculator use for CO2?
It uses 44.0095 g/mol for carbon dioxide. This value supports chemistry calculations where higher precision is helpful, especially for lab conversions.
2) Why does ppm(v) conversion need temperature and pressure?
ppm(v) is a mixing ratio, not a mass concentration. Temperature and pressure set the gas density, which lets the ideal gas relationship convert ppm(v) into mg/m³.
3) Is mg/m³ from ppm(v) exact in real air?
It is an ideal-gas estimate. At typical indoor conditions the error is usually small, but high pressures, very low temperatures, or non‑ideal behavior can change results.
4) What does the fuel method assume?
It assumes complete combustion: every gram of carbon becomes CO2. Real systems may emit CO, soot, or leave unburned fuel, which lowers actual CO2 produced.
5) How do I choose carbon percentage for fuel?
Use a measured value if available. Otherwise, use a reasonable estimate for your fuel type. Gasoline and diesel are often near the high‑80% range by mass.
6) Why do I see both normalized and converted outputs?
Normalized outputs help you audit conversions. For example, masses are converted to grams internally to apply molar mass consistently, then displayed in your selected unit.
7) What should I do if results look wrong?
Check units first, then confirm decimals and chosen method. Try the example table values to validate. If ppm(v) is used, verify temperature and pressure inputs.