Methane is a chemical compound with the formula CH4. It is the first element of the alkane hydrocarbon family and is the main constituent of natural gas. The relative abundance of methane on Earth makes it an attractive fuel, although capturing and storing it poses challenges due to its gaseous state under normal conditions for temperature and pressure.
CAS no: 74-82-8
Properties
Generic Properties
| Property | Value | Unit |
|---|---|---|
| Chemical Formula | CH4 | - |
| Molecular Weight | 16.043 | - |
| Heat of Combustion | 50028.8 | kJ/kg |
| Boiling Point | 111.66 | K |
| Freezing Point | 90.67 | K |
| Flash Point | 85.37 | K |
| Auto Ignition | 873.15 | K |
| LEL | 5 | vol % |
| UEL | 15 | vol % |
Critical Properties
| Property | Value | Unit |
|---|---|---|
| Critical Temperature | 190.58 | K |
| Critical Pressure | 46.04 | bar |
| Critical Volume | 99.3 | cm3/mol |
| Critical Density | 0.1616 | g/cm3 |
| Critical Z | 0.288 | - |
| Accentric Factor | 0.011 | - |
Temperature Dependent Properties
Specific Heat
The specific heat at constant pressure can be calculated with the formula:
| Constant | Gas | Liquid | Solid |
|---|---|---|---|
| A | 34.942 | -0.018 | 5.27 |
| B | -0.039957 | 1.1982 | 0.71386 |
| C | 0.00019184 | -0.0098722 | -0.0032653 |
| D | -0.000000153 | 0.00003167 | - |
| E | 3.9321E-11 | - | - |
| T max(K) | 50 | 92 | 21 |
| 1500 | 172 | 90 |
Heat of Formation
The heat of formation can be calculated with the formula:
| Constant | Value |
|---|---|
| A | -63.383 |
| B | -0.042512 |
| C | 0.000017525 |
| T min(K) | 298.15 |
| T max (K) | 1000 |
Viscosity
The viscosity can be calculated with the formula:
For liquid
For Gas
| Constant | Gas | Liquid |
|---|---|---|
| A | 3.8435 | -7.3801 |
| B | 0.4011 | 319.25 |
| C | -0.00014303 | 0.0479 |
| D | - | -0.0001412 |
| T min(K) | 91 | 91 |
| T max(K) | 850 | 191 |
Heat of Vaporization
The heat of vaporization can be calculated with the formula:
| Constant | Value |
|---|---|
| A | 10.312 |
| n | 0.265 |
| T min(K) | 90.67 |
| T max(K) | 190.58 |
Thermal Conductivity
The thermal conductivity can be calculated with the formula:
| Constant | Gas | Liquid |
|---|---|---|
| A | -0.00935 | 0.2269 |
| B | 0.00014028 | 0.00044275 |
| C | 3.318E-08 | -5.2397E-06 |
| T min(K) | 97 | 91 |
| T max(K) | 1400 | 181 |
Liquid Density
The Liquid Density can be calculated with the Equation:
| Constant | Value |
|---|---|
| A | 0.16 |
| B | 0.2881 |
| n | 0.277 |
| T min(K) | 90.67 |
| T max(K) | 190.58 |
Saturation Pressure
The Saturation Pressure can be calculated with the Antoine Equation:
| Constant | Value |
|---|---|
| A | 6.84566 |
| B | 435.621 |
| C | 271.361 |
| T min(C) | 90.67 |
| T max(C) | 190.58 |
Diffusion Coefficient at Infinite Dilution in Water
The Diffusion Coefficient at Infinite Dilution in Water can be calculation:
| Constant | Value |
|---|---|
| A | -1.6865 |
| B | -920.576 |
| T Min(K) | 274 |
| T Max(K) | 394 |
Diffusion Coefficient in Air
The Diffusion Coefficient in Air can be calculated with the Equation:
| Constant | Value |
|---|---|
| A | -0.09564 |
| B | 0.00069948 |
| C | 1.2497E-06 |
| T min(K) | 200 |
| T max(K) | 1000 |