Baking Soda + Vinegar = Lift Off
Purpose: To determine the right amount of baking soda and vinegar to produce the most gas and the highest launch of a film canister rocket.
Question:
Hypothesis:
Background:

Reaction equation
Step 1:
NaHCO
3
+ HC
2
H
3
O
2
→ NaC
2
H
3
O
2
+ H
2
CO
3
Vinegar + Baking Soda  sodium acetate + carbonic acid
Because carbonic acid is unstable it undergoes another reaction

Step 2
H
2
CO
3
→ H
2
O + CO
2
Carbonic acid  water and carbon dioxide

Total Reaction:
NaHCO
3
+ HC
2
H
3
O
2
→ NaC
2
H
3
O
2
+ H
2
O + CO
2
Vinegar + Baking Soda  Sodium Acetate + water + Carbon dioxide

You must
Determine the kind of reaction present in step 1
Determine the kind of reaction present in step 2
Balance the equation in total reaction.
Write the reactants and products for the total reaction
Materials:

Plastic film canister

Optional: Construction paper, any color
(1 sheet); transparent tape; and scissors.

Masking tape or painter's tape.

Permanent marker

Metric ruler,

Baking soda

White vinegar

Measuring spoon, 1/8 tsp.

Measuring spoon, 1 tsp.

Bowl

Water

Spoon

Safety goggles

Lab notebook
Procedure:
Preparing Your Test Area
1.
Create a data table in your lab notebook so that you can keep track of the data that you collect. It should look like Table 1 below.
2.
If you want, you may decorate your film canister, which will be the body of your rocket.

a.
You could take a piece of construction paper and wrap it around the film canister. Make sure to wrap along the short side of the paper, about 2 millimeters below the lip of the canister, and make sure that the lid is not enclosed or covered by the tube of paper. Wrap the paper neatly and evenly along the canister and use the scissors to remove the excess paper from the bottom.
Secure the paper with a few pieces of transparent tape. b.
Make sure it is still easy to put the lid on the canister.
3.
Now go o to your test site. Prepare the test site so you will be able to measure how high the rocket goes. a.
Put a long piece of masking tape or painter's tape on the wall, just 15 centimeters (cm) from the ground. The piece of tape should be about 50 cm long. b.
Then put a long piece of tape every 15 cm up after that until you reach the top of the wall (or about 4 meters [m] high). Ask an adult to help put up the higher pieces of tape (possibly using a ladder may be needed). c.
Use the permanent marker to label each piece of tape. For example, the first piece should be labeled "15 cm," the next should be "30 cm," and so on.
Preparing the Rocket
1.
Now prepare the baking soda for the rocket. a.
Place 1 teaspoon (tsp.) of baking soda in the bowl. Carefully add 1/8 tsp. of water to the baking soda and mix it in using the spoon. This should wet the baking soda enough so that you can pack it into the depression on the inside of the canister lid. b.
Turn the film canister lid over and tightly pack the inside of the depression with the damp baking soda, as shown in Figure 2 below. c.
Briefly turn the lid upside-down and make sure that the baking soda does not fall out. If the baking soda all falls out, then add a little bit more water to the baking soda and mix it in. Try to add only a minimal amount of water to the baking soda in order to make it stick together inside the lid. d.
Record the amount of baking soda that you used in the data table in your lab notebook.
2.
Now prepare the vinegar for the rocket. a.
Add 1 tsp. of vinegar to the canister at a time, filling it almost to the top. You need to add as much vinegar to the canister as possible without the vinegar and the baking soda coming into contact when you eventually snap the lid onto the canister, as shown in Figure 3 below. ( Tip:
Depending on the exact canister, this may be around 5 tsp. of vinegar.) This might take a little trial and error, but be patient and keep trying. b.
Keep careful track of and record the amount of vinegar in the data table in your lab notebook.
3.
Go over to the outdoor area where you put tape strips on the wall and prepare to have your experiments videotaped or watched by a volunteer. a.
If you want to videotape your experiments, use a tripod or an adult volunteer to set up the video camera so that it has in its viewfinder the spot where you will launch your canister rocket and the tape strips on the wall. Have the camera start recording at the beginning of step 4, and stop recording at the end of step 6. b.
If you do not have a video camera, you can alternatively ask a volunteer to watch the reactions to help you figure out how high the canisters go.
4.
Launch your rocket. a.
Put on your safety goggles. Stoop down near the ground on a flat, hard spot and quickly snap the lid onto the canister to seal it. Immediately turn the canister over so the lid is on the ground, and quickly move away. b.
Wait for the chemical reaction to occur (the time depends on the amount of baking soda and vinegar you are using). c.
When the lid finally pops off, the rocket should overcome gravity and launch. You and your volunteer should watch to see how high it goes and record the launch height in the data table in your lab notebook.
5.
Carefully rinse out the lid and canister with water. a.
If your canister is decorated, make sure that the construction paper does not get too wet.
6.
Repeat steps 1–5 two more times, always recording the launch height in the data table in your lab notebook. a.
It is a good idea to perform at least three trials of each experiment so that you know your results are accurate and reproducible.

7.
Decrease the amount of vinegar in the canister by 1 tsp. and repeat steps 1–6. Record all of the data in the data table in your lab notebook.
8.
Once again, reduce the amount of vinegar by 1 more tsp. and repeat steps 1–6. Always record all of the data in your lab notebook.
9.
Now that you have investigated the effect of the amount of vinegar on launch height, investigate how the amount of baking soda affects the launch height. a.
Reduce the amount of baking soda to ½ tsp. and repeat steps 1–6, with the original amount of vinegar used for your first vinegar trial. Adjust and use just enough water for the baking soda to stick to the depression in the lid. Record all of your data in the data table in your lab notebook. b.
Repeat step 9a but this time reduce the amount of baking soda to ¼ tsp.
Data:
Table 1
Amount of Baking
Soda (tsp)
Amount of vinegar
(tsp) trial
1
2
3
Launch
Height (cm)
1
2
3
1
2
3
Average Launch
Height (cm)
Results:
1.
Average the launch height data for each set of trials that you recorded in your data table. (The amount of baking soda and vinegar used in a set of trials should be the same between the different trials.) Write the averages in the far right column of your data table.
2.
Using the averages data in your data table, make two line graphs. One graph should have the average launch height for when the amount of baking soda stayed the same (all 1 tsp.) but you changed the amount of vinegar. The second graph should have the average launch height for when you kept the amount of vinegar the same but changed the amount of baking soda. a.
You can make your plots by hand on graph paper, or if you would like to make your plots online, try the following website: Create a Graph . b.
For one graph, label the x-axis "Amount of Vinegar (tsp.)." For the other graph, label the x-axis
"Amount of Baking Soda (tsp.)." c.
For both graphs label the y-axis "Average Launch Height (cm)." d.
Plot the average launch height for the varying amounts of vinegar or baking soda on each graph.
Conclusion:
Analyze your graphs and try to explain your results. Make sure you put your answer into paragraph form. a.
Based on your results, what is the ideal amount of baking soda and vinegar to use? b.
Which variable affects the launch height the most, vinegar or baking soda? c.
Do you see any trends in your data? If so, can you explain them? Do your trends correlate with other observations you made, such as whether it took a longer or shorter amount of time for a rocket to launch