Chemical, physical and thermal properties of methanol, CH 3 OH (also called carbinol, wood alcohol, hydroxymethyl and methyl alcohol). Phase diagram included.
Methanol, CH3- OH , It is a colorless, highly volatile liquid with a pungent, slightly sweet odor, similar to, but slightly milder and sweeter than, ethanol .
Methanol is toxic and can cause blindness. Vapors are slightly heavier than air and may explode if ignited.
Methanol is used to manufacture chemicals, to remove Water in automotive and aviation fuels, as a solvent for paints and plastics, and as an ingredient in a wide variety of products.
The phase diagram for methanol is shown below the table.
Chemical, physical and thermal properties of ethanol:
Values are given for net at 25 O C /77 O F / 298 K and 1 bara, if not another phase, temperature or pressure indicated.
| Property | Valor | Unit | Valor | Unit | Valor | Unit | Valor | Unit | |||
| Acidize (pK a1 ) | 15,3 | ||||||||||
| auto-ignition temperature | 737 | iso-15552-srie-ke | 464 | °C | 867 | °F | |||||
| Boiling point | 337,85 | iso-15552-srie-ke | 64,7 | °C | 148,5 | °F | |||||
| critical density | 8,7852 | mol/dm 3 | 281 | kg/ m3 | 0,546 | slug/foot 3 | 17,6 | lb/ft 3 | |||
| Critical Pressure | 8.22 | MPa=MN/ m2 | 82,2 | bar | 81,1 | cash machine | 1192 | psi = lb f /in 2 | |||
| Critical temperature | 513,4 | iso-15552-srie-ke | 240,2 | °C | 464,4 | °F | |||||
| Critical Volume | 114 | cm3 / mol | 0,003552456 | m3 / kg | 1.831 | foot 3 /slug | 0,05690 | foot 3 /lb | |||
| Density (gas) at 0.17 bar | 6,87 | mol / m3 | 0,220 | kg/ m3 | 0,00043 | slug/foot 3 | 0,0137 | lb/ft 3 | |||
| Density (liquid) | 24540 | mol / m3 | 786,3 | kg/ m3 | 1,526 | slug/foot 3 | 49.09 | lb/ft 3 | |||
| Flammable, gas and liquid | sim | ||||||||||
| Flash point | 284 | iso-15552-srie-ke | 11 | °C | 52 | °F | |||||
| Gas constant, individual – R | 259,5 | J/kg K | 0,07208 | Wh/(kg K) | 1552 | [ft lb f /slug °R] | 48,23 | [ft lb f /lb °R] | |||
| Gibbs formation free energy (gas) | -163 | kJ/mol | -5087 | kJ/kg | -2187 | Btu/lb | |||||
| Heat (enthalpy) of combustion (gas) | 726,1 | kJ/mol | 22661 | kJ/kg | 9.7 | Btu/lb | |||||
| Heat (enthalpy) of combustion (liquid) | -727 | kJ/mol | -22689 | kJ/kg | -9,8 | Btu/lb | |||||
| Heat (enthalpy) of formation (gas) | -205 | kJ/mol | -6398 | kJ/kg | -2751 | Btu/lb | |||||
| Heat (enthalpy) of formation (liquid) | -239 | kJ/mol | -7459 | kJ/kg | -3207 | Btu/lb | |||||
| Heat (enthalpy) of fusion at -143°F/-97°C | 3,18 | kJ/mol | 99 | kJ/kg | 42,67 | Btu/lb | |||||
| Heat (enthalpy) of evaporation | 37,34 | kJ/mol | 1165 | kJ/kg | 501.01 | Btu/lb | |||||
| Specific heat capacity, Cp (gas) at 0.17 bar | 116 | J/mol K | 3,62 | kJ/kg K | 0,865 | Btu/lb°F ou cal/g K | |||||
| Specific heat capacity, Cp (net) | 81,2 | J/mol K | 2,53 | kJ/kg K | 0,605 | Btu/lb°F ou cal/g K | |||||
| Specific heat capacity, Cp (solid) at -148°F/-100°C | 105 | J/mol K | 3,28 | kJ/kg K | 0,783 | Btu/lb°F ou cal/g K | |||||
| Specific heat capacity, Cv (gas) at 0.17 bar | 94,5 | J/mol K | 2,95 | kJ/kg K | 0,704 | Btu/lb°F ou cal/g K | |||||
| Specific heat capacity, Cv (net) | 67,9 | J/mol K | 2.12 | kJ/kg K | 0,506 | Btu/lb°F ou cal/g K | |||||
| ionization potential | 10,84 | eV | |||||||||
| log K OW (Octanol/Water Partition Coefficient) | -0,77 | ||||||||||
| Fusion point | 175,55 | iso-15552-srie-ke | -97,6 | °C | -143,7 | °F | |||||
| Molecular weight | 32.042 | g/mol | 0,07064 | lb/mol | |||||||
| Solubility in water | 1000 | mg/ml | (Miscible in water) | ||||||||
| Speed of sound in gas, at 0.17 bar | 297 | EM | 974 | pes/s | 665 | wed/h | |||||
| Speed of sound in liquid | 1100 | EM | 3608 | pes/s | 2464 | wed/h | |||||
| Specific Gravity (gas) (relative to air) | 1.11 | ||||||||||
| Specific Gravity (liquid) (relative to water) | 0,79 | ||||||||||
| Specific Heat Ratio (gas) - cp/hp | 1,23 | ||||||||||
| Specific Heat Ratio (liquid) - cp/hp | 1,20 | ||||||||||
| Specific Volume (gas) 0.17 bar | 0,146 | m3 / mol | 4,55 | m3 / kg | 2342,63 | foot 3 /slug | 72,81 | foot 3 /lb | |||
| Specific Volume (liquid) | 0,0000408 | m3 / mol | 0,00127 | m3 / kg | 0,655 | foot 3 /slug | 0,0204 | foot 3 /lb | |||
| Standard molar entropy, S° (gas) | 240 | J/mol K | 7,49 | kJ/kg K | 1,79 | Btu/lb °F | |||||
| Standard molar entropy, S° (net) | 127 | J/mol K | 3,96 | kJ/kg K | 0,95 | Btu/lb °F | |||||
| Superficial tension | 22.07 | dinas/cm | 0,02207 | N/m | |||||||
| thermal conductivity | 0,202 | A/m°C | 0,116713 | Btu/h ft °F | |||||||
| triple point pressure | 1,86*10 -7 | MPa=MN/ m2 | 1,86*10 -6 | bar | 1,84*10 -6 | cash machine | 2,70*10 -5 | psi = lbf/pol 2 | |||
| triple point temperature | 175,50 | iso-15552-srie-ke | -97,7 | °C | -143,77 | °F | |||||
| Vapor pressure (saturation) | 0,0169 | MPa=MN/ m2 | 127,0 | mm Hg | 0,1671 | cash machine | 2,46 | psi = lbf/pol 2 | |||
| Viscosity, dynamics (absolute) | 0,544 | cP | 365,55 | [lbm/pes*10 -6 ] | 11,36 | [lbf s/pé 2 *10 -6 ] | |||||
| Kinematic viscosity | 0,692 | cSt | 7.4 | [foot 2 /s*10 -6 ] | |||||||
Methanol is a liquid under standard conditions. However, at low temperatures and/or very high pressures it becomes a solid.
The phase diagram for methanol shows phase behavior with changes in temperature and pressure. The curve between the critical point and the triple point shows the boiling point of methanol with changes in pressure. It also shows saturation pressure with changes in temperature.
Source: https://www.engineeringtoolbox.com/methanol-methyl-alcohol-properties-CH3OH-d_2031.html
