實驗目的

• Understanding what is Hydrogen Peroxide and its decomposition, and extra topic

實驗名稱

• Elephant toothpaste

教學目標（彈性) → about 20-30 mins

• Introduction to equations and balancing them, learning the decomposition of Hydrogen Peroxide (introduction to peroxides), Introduction to catalyst/catalase

物品：

• Hydrogen Peroxide (ideally concentration of 6%, which is a bit more than the ones found in pharmacies, which is generally 3%, but 3% should work fine) (According to some sources, the 6% type can sometimes be purchased at beauty stores as the higher concentration will allow hairs to be lightened)

• Yeast (as catalyst, though wikipedia also suggested an alternative of Potassium Iodide)

• Dish Soap

• Warm Water

• Soda Bottle (to contain and to make the dramatic effect) (ideally the 16oz variant)

• Food Coloring

Optional :

• Funnel

• Goggles

Procedure:

• Pour 100-120 ml of H₂O₂ into the bottle

• Add food coloring and dish soap, shake to even it out

• In another cup, add a tablespoon of yeast and about 3 tablespoon of warm water, mix (should have sort of a melted vanilla feel)

• When ready, carefully pour the yeast into the bottle, and watch for the magnificent explosion

Precaution:

• If the concentration of the hydrogen peroxide is at 6%, advise the students to not touch the foam produced due to safety concern of unreacted hydrogen peroxide

• Although produced in the small amounts, the experiment is an exothermic reaction with the byproduct being oxygen, so any thing that can cause flame should be at a distance

• Don’t drink, play with, or splash someone with anything

• Don’t be too close to the foam produced at the beginning

大象牙膏

・材料：雙氧水、酵母粉、溫水、色素、寶特瓶及洗碗精

・原理：雙氧水反應會產生氧氣和水，加入酵母，讓雙氧水迅速產生氧氣。 加入洗碗精是為了產生泡沫，反應產生的氧氣如同吹泡泡一般，讓泡沫大量產生，而形成如同牙膏狀的泡泡。

・步驟：

1. 將雙氧水、色素、洗碗精倒入其寶特瓶中

2. 將溫水及酵母混合，並將其倒入水中。

3. 成功了～

故事說了，實驗做了，大象也有牙膏了，讓我們複習一下吧！

請把故事中的人物列出來：

・畫畫看：看過了不同物質上演的好戲後，我們複習一下他們的長相吧！

小氫氫（H）

樂氧氧（O）

雙氧水（樂氧氧想和其他人做朋友）

水（最穩定，不喜歡別人進來）