| Physical State | Liquid | - | - |
| Appearance | Clear liquid | - | - |
| Color | Colorless | - | - |
| Odor | Pungent, irritating odor | - | - |
| Molecular Weight | 36.46 | - | - |
| Molecular Formula | HCl | - | - |
| Chemical Family | Inorganic Acid | - | - |
| pH (at 1.0 N Hydrochloric Acid) | 0.10 | - | - |
| pH (at 0.1 N Hydrochloric Acid) | 1.1 | - | - |
| pH (at 0.01 N Hydrochloric Acid) | 2.02 | - | - |
| pH (at 0.001 N Hydrochloric Acid) | 3.02 | - | - |
| pH (at 0.0001 N Hydrochloric Acid) | 4.01 | - | - |
| Melting Point (at 39.17wt% solution) | -25.4 | °C | - |
| Freezing Point (at 10.81% solution) | -17.14 | °C | - |
| Freezing Point (at 20.69% solution) | -62.25 | °C | - |
| Freezing Point (at 31.24% solution) | -46.2 | °C | - |
| Freezing Point (at 39.17% solution) | -25.4 | °C | - |
| Flash Point | Not flammable | - | - |
| Vapor Pressure | 413.6 | mmHg | - |
| Vapor Density (air=1) | 1.268 | - | - |
| Specific Gravity (water=1) | 1.05 - 1.18 | - | - |
| Density (at 15°C, 10.17wt% solution) | 1.05 | - | - |
| Density (at 15°C, 20wt% solution) | 1.01 | - | - |
| Density (at 15°C, 29.57wt% solution) | 1.15 | - | - |
| Density (at 15°C, 39.11wt% solution) | 1.2 | - | - |
| Water Solubility (at 0°C) | 82.3 | g/100g | - |
| Water Solubility (at 30°C) | 67.3 | g/100g | - |
| Water Solubility (at 40°C) | 63.3 | g/100g | - |
| Water Solubility (at 50°C) | 59.6 | g/100g | - |
| Water Solubility (at 60°C) | 56.1 | g/100g | - |
| Water Solubility (at 25°C) | 1.2 | g/100g | - |
| Odor Threshold | 0.255 - 10.06 | ppm | - |
| Evaporation Rate (butyl acetate = 1, ether=1) | max. 1.00 | - | - |
| Volatility | 9 - 36 | vol% | - |
| Flammability (solid, gas) | Not flammable | - | - |
| Lower Flammability Level (air) | Not flammable | - | - |
| Upper Flammability Level (air) | Not flammable | - | - |
| Viscosity (liquid at 118.16°K) | 0.405 | cPs | - |
| Viscosity (vapor at 273.06°K) | 0.0131 | cPs | - |
| Viscosity (vapor at 523.2°K) | 0.0253 | cPs | - |
| Surface Tension (at 118.16°K) | 23 | mN/cm | - |