36. A student prepared solutions of (i) an acid and (ii) a base in two separate beakers. She forgot to label the solutions and litmus paper is not available in the laboratory. Since both the solutions are colourless, how will she distinguish between the two?
Steps: Use an appropriate indicator: phenolphthalein (colourless in acid, pink in base) or turmeric (colour change with base). Or react with carbonate to detect acid by CO₂ evolution.