Why does a titrated sample that is fuschia with phenolphthalein turn colorless when the solution is blown into? HINT: Use chemistry and properly balanced chemical equations to support your statement.

Answer 1

When you blow into the solution you are adding CO2 to the solution. The CO2 reacts with water to form H2CO3 and that ionizes to produce H^+. That lowers the pH of the solution and the phenolphthalein turns the acid color which is colorless. You write the equations.