Liquid Ethylene Density Calculator

Liquid ethylene density describes the mass contained in a unit volume of condensed ethylene, also called ethene or C2H4. Because ethylene is a gas under ordinary room conditions, it remains liquid only at very low temperature or under pressure. This calculator covers the saturated-liquid region from approximately the melting point at -169 °C to the normal boiling point near -104 °C. It reports the same estimate in g/cm³ and kg/m³, two units commonly used in laboratory work, storage calculations, process engineering, and transport planning. The estimate uses a smooth temperature correlation fitted to representative saturated-liquid property data. Density falls as temperature rises because thermal motion increases the average spacing between molecules. The relationship is slightly curved rather than perfectly linear, so the calculator includes a quadratic temperature term. At the cold end of the range, liquid ethylene is denser; close to its boiling point, the liquid has expanded and the density is lower. Multiplying g/cm³ by 1,000 gives kg/m³, so both displayed answers describe exactly the same physical density. Density data can help convert a known liquid volume to mass with mass equals density times volume. It can also support tank inventory estimates, pump calculations, material balances, and comparisons with other light hydrocarbons. The result is an engineering estimate, not a replacement for a property database selected for a specific pressure and composition. Commercial ethylene may contain impurities, and a pressurized or subcooled liquid can differ from the saturated value at the same temperature. Use a measured bulk temperature that represents the liquid, not the surrounding air. Keep the input inside the supported interval because extrapolating a fitted correlation beyond the phase range can create physically misleading results. For safety-critical design, custody transfer, or regulatory work, verify the value against an authoritative equation of state and include the actual system pressure. Within its stated limits, this calculator provides a quick, consistent way to estimate liquid ethylene density and convert between practical metric units.