This set includes two 15 ml bottles of phenolphthalein solution, providing a total of 30 ml. Phenolphthalein (C₂₀H₁₄O₄) is a classic pH indicator widely used in chemistry labs and classrooms. In acidic and neutral solutions, it remains colorless, but in basic solutions (pH ≈ 8.2–10), it develops a vivid pink color, making it perfect for titrations, acid-base reaction demonstrations, and teaching pH concepts. The small, convenient bottles are ideal for portioned use, reducing waste and improving storage life. Each container is securely sealed and clearly labeled for safe handling.