Secret writing

The video tutorial demonstrates how goldenrod paper can be used as an acid-base indicator. It explains the importance of using real goldenrod paper and original Windex with ammonia to create a visible reaction. By writing on the paper with wax, the reaction can be controlled, as the wax prevents ammonia from reaching the paper. The tutorial also highlights the reversible nature of the reaction, showing how a hair dryer can return the paper to its original color by evaporating the ammonia.

How does the wax affect the reaction between ammonia and the goldenrod paper?

What happens when a hair dryer is used in this experiment?