Fly ash is the ash residue from coal combustion. The silica in fly ash can be used to improve the compressive strength of concrete. High-quality nanosilica can be produced through the synthesis process from fly ash waste. The materials used in this study include fly ash, HCl solution, NaOH, aquadest, and Kangen water. Variations in HCl molarity (1 M, 1.5 M, and 2 M) were applied to determine th…