✔ 最佳答案
1. Pours half cup of water in the tray
2. Drops 10 drops 碘酒 is even in the tray and the water mix
3. Extrusion lemon juice in the cup
4. Cuts out the paper just may put on the tray the size
5. Soaks the paint brush in the lemon juice, then writes the writing on the paper
which oneself likes
6. After finishes, dryings the paper
7. Finally the paper which dryings lays aside to dissolves has the idodine fluid
in the tray
8. On the paper besides the part which writes presents the achromatic color, other
parts all are the royal purple.
The paper content has the starch, meets and the idodine responded
forms the idodine starch member, but presents the royal purple; When
vitamin C and idodine response, can have the colorless phenomenon.
This is because in the lemon includes vitamin C, therefore to the
lemon juice writes the part cannot have the color change.