Are you ready for a ‘Does It Float?” science experiment? We have done experiments with Floating Eggs, and Sinking Oranges, now we are going to experiment with pop cans (or soda cans depending on what part of the world you live in)!
Grab your supplies and try this experiment with us. Just be sure all your cans are the same shape, size and volume (12 FL OZ or 355 mL), and that you have a variety of different types of pop including regular and diet. The experiment is a simple yet effective density experiment that will take only about 5 minutes to perform.
Let’s find out which ones will float in water and which ones will sink!
JUMP TO SECTION: Instructions | Video Tutorial | How it Works
- Large Bucket or Container
- Unopened Pop Cans (use a variety of pop, some regular and some diet)
Floating and Sinking Pop Cans Experiment Instructions
Experiments Setup – Start with some observations about the cans. Are they the same size? What about the same shape? List the ways the cans are the same. Then list the ways the cans are different. Now ask a few more questions. Do you think the cans will sink or float when placed in water? Do you think they will all behave the same way (meaning will they all float, or will they all sink)? Write down your hypothesis (prediction) and then follow the steps below.
Step 1 – Begin by filling a large container with water. The water should be deep enough so you can easily tell which cans are floating and sinking.
Step 2 – Slowly place each can into the water one at a time. Make sure to tip the can on it’s side when you are placing it in the water so no air is trapped at the bottom of the can. If there is a bubble of air trapped at the bottom of the can, the results of the experiment will be impacted.
Step 3 – Observe the cans as you place them in the water. Are they all behaving the same way? Which cans are floating? Which cans are sinking?
Step 4 – After all the cans are in the water, examine the results and try to figure out why some of the cans float to the top and others sink to the bottom. Find out the answer in the how does this experiment work section below.
Why Do Some Pop Cans Float and Others Sink Science Experiment Step by Step Instructions
How Does the Floating and Sinking Pop Cans Science Experiment Work
Why do some cans of pop sink while some float? All of the cans have the exact same shape, size and volume. Density is the key to this experiment! Density is a measure of the mass per unit volume of a substance. Water has a density of 1 g/mL (g/cm3). Objects will float in water if their density is less than 1 g/mL. Objects will sink in water if their density is greater than 1 g/mL. The cans of diet pop are less dense than water, so they float. The cans of regular pop are more dense than water so they sink.
Now you may be wondering why the density of the cans of pop is different. The answer lies in the type of sweetener used in each pop. Sugar is used to sweeten regular pop, a lot of sugar. This large quantity of sugar causes the can to become more dense than water. Artificial sweeteners are used in diet pop. However, a much smaller amount of artificial sweetener is used which causes the can to be less dense than water.
There you have it, even though the cans were the exact same shape, size and volume (335mL) the densities were different due to the sugar!
I hope you enjoyed the experiment. Here are some printable instructions:
Floating & Sinking Pop Can Experiment
This was helpful
Kaelin Simon says
This really helped me with my kids’ experiment. Now she will be able to do it on her on.
this was the reason why i got first place in the science fair thanks for sharing great science fair ideas best web ever keep up good work :).
Stephanie Oliver says
My daughter is doing this for a science fair project this year, we used regular soda and diet and the diets floated, regulars sank.. However afterwards we threw in a caffeine free regular soda and it floated. Similar in grams of sugar than regular soda but still floated… I’m stumped. All are equal size and weight.
Mrs. Gill says
We tried this in my science class. We found out the sugar in the regular soda caused it to be more dense than the diet soda (which has artificial sweetener). We had fun with this experiment!
Hunter Randolph (Not taken) says
This is one of my favorite experiments ever!!!!!! I´ve done it with my son and he loves it too.
Hunter Randolph (Not taken) says
It has something to do with the caffeine. There is not a lot of caffeine in diet sodas, so it makes them float a little. Did the caffeine free sodas float at the top while the diet sodas floated under the water.