Elephant Toothpaste
Material needed:
hydrogen peroxide, detergent, manganese dioxide, lead oxide, graduated cylinder, tablespoons, electronic scale, watch glass, pipette, paper, large container
Experiment date: 10/14/24
Written by: Sophia Han
Step 1
Measure 0.5 g of lead oxide with the electronic scale and put it into the graduated cylinder.
(the paper can be used to add the powder).
Step 2
Squirt in 0.5 mL of detergent using a pipette into where the catalyst (lead oxide) is in.
Step 3
In a separate graduated cylinder, measure 20 mL of hydrogen peroxide.
Step 4
Repeat Steps 1~3 with manganese dioxide instead of lead oxide. Label them to differentiate between the two.
Step 5
Add the 20 mL of hydrogen peroxide measured into each beaker at the same time.
DISCUSSION
Objective:
1. Visualize gas production
2. Observe a chemical reaction: 2H2O2 (aq) → 2H2O (l) + O2 (g)
Results:
The formation of bubbles can be observed, producing foam and heat. Because the elephant toothpaste experiment is qualitative, we decided to measure the time it takes for the foam to overflow the graduated cylinder. On average, the time of overflow was faster in lead oxide compared to manganese dioxide by 5 seconds.
*Make sure not to touch the foam with your bare hands!
Explanation:
The elephant toothpaste experiment is essentially the decomposition, or the breaking down of hydrogen peroxide into oxygen and water. Because the detergent traps the oxygen gas and produce bubbles, foam is created.
This is a relatively slow reaction, but due to the presence of lead oxide and manganese dioxide, which act as catalysts, the rate of reaction is sped up.
Technically, we can find out which catalyst works better by observing which one has a shorter time of overflow.
What is a catalyst?
A catalyst is a substance that speeds up a chemical reaction without being used.
It lowers the activation energy (i.e. the minimum amount of energy required for a reaction to take place) of a reaction by providing an alternate pathway. As less energy is required for the reaction, the number of successful collisions, which causes the rate of reaction to increase.
Gallery
