Ethanol concentration estimator based on relative density

Ethanol Concentration Estimator

Author: Sarai J. Carrasco Miranda

Creation Date: September 2026

Operating Condition: Measurement temperature must be at 20 °C (68 °F) relative to water at 20 °C.

Description and Instructions

This web application calculates the weight percentage concentration of ethanol in aqueous solutions using specific gravity measurements at 20 °C.

How to use:

1. Measure the specific gravity of the ethanol-water solution at 20 °C.
2. Enter the measured specific gravity value in the text field below (valid range: 0.7893 to 0.9982).
3. Click "Calculate Concentration" to perform the automated calculation and visualize your point on the reference curve.

Mathematical Model

Experimental data are numerically interpolated from standard ethanol-water thermodynamic tables (CRC Handbook / Perry's):

$$C(d) = C_i + \frac{C_{i+1} - C_i}{d_{i+1} - d_i} (d - d_i)$$

Where d_i and C_i are the adjacent data points for specific gravity (SG_20/20) and concentration (% w/w) respectively.

Estimation Calculator

Specific Gravity (SG 20/20):

Fitted Curve and Data Validation