Evaluation of viscosity and surface tension of low-volume samples using glass capillary

Abstract

Abstract In this paper, methods for measuring the viscosity and surface tension of low-volume liquid samples are proposed. Viscosity is measured by recording the motion of a liquid driven by surface tension through a horizontal glass capillary tube. Surface tension is determined by connecting a container of a constant volume to the distal end of the capillary tube and measuring the penetration distance of the liquid entering via the proximal end. Sucrose solutions of various concentrations (0–50 wt%) were measured as samples, and the determined viscosities were confirmed to be consistent with the tabulated values provided in the Handbook of Chemistry. The surface tension was found to be constant within the measurement sensitivity of the device regardless of the sucrose concentration.