Article puts under scrutiny a method of measuring the speed of sound in liquids via a laser projection of a standing wave. The range of application of the particular method was examined. A procedure of conducting the demonstration has been formulated based on the analysis of the impact of several parameters of the demonstration setup: particular vessel, depth of the liquid, position of the cone of light with regards to the stationary wave and particular sample used were all evaluated with regards to the quality of the demonstration as well as reliability of the measurement. Applying the procedure in order to quantitatively determine the concentration of a solution has been attempted, as well as usefulness of the method in a demonstration context – examined. As a conclusion, the potential of applying the method for demonstration has been discussed and an instruction for such
demonstration has been produced.