Dialog 1

Edo: There are many items here. What are you going to do with them?

Cindy: I am going to experiment on invisible ink.

Edo: Invisible ink? How can it be?

Cindy: Look at what I will do.

Edo: Sure.

Cindy: O.K., I will prepare a lemon cut into half, white paper, water, a spoon, bowl, cotton bud, and lamp or light bulb.

Edo: Why do you use lemon juice?

Cindy: Lemon juice is an organic substance that oxidizes and turns brown when heated. Diluting the lemon juice in water makes it very hard to notice when you apply it on paper. No one will be aware of its presence until it is heated and the secret message I revealed.

Edo: That's interesting! I'd like to try.

Cindy: Sure. Go ahead 

Work in pairs.
Complete the following statements based on the dialogs in Activity 7.
hen, read the statements aloud, in turns. 

Lemon juice will ____