Dissolve a Seashell Experiment

Can you dissolve a seashell?  What happens when you put a seashell in vinegar?

In this experiment, learn about why seashells dissolve in vinegar and talk to your children about the effects of ocean acidification.

Start collecting sea shells for this activity the next time you head to the beach!

Dissolve a Seashell Experiment

What you need
Step by step
  • White vinegar
  • Sea Water (approx 1 1/2 teaspoons salt per 1 cup water)
  • Clear glass or plastic jars/cups
  • Seashells

    1) Set out several containers.  Add a seashell to each container.  

    You could have multiple containers with different types of shells to investigate whether the type of shell affects how fast the shell dissolves. 

    2) Pour your seawater into one container and cover the shell completely.  This will act as the control. Label the container ‘seawater’.

    3) Pour vinegar over the remaining seashells to cover each completely.

    4) Set the jar aside and observe what happens. Check on your seashells periodically (every 6 hourly) and observe the changes.



    As the shells react with the vinegar, they will become more and more fragile until they fall apart. Thinner shells will react quicker, hence the white shell breaks but not the thicker coloured shell.

    This experiment simulates the effects of ocean acidification. Ocean acidification is a change in the pH of seawater, which is normally around neutral. As the level of carbon dioxide in the atmosphere rises and combines with water in the ocean it forms carbonic acid and lowers the pH of seawater, making it more acidic.

    The burning of fossil fuels is the main culprit for the increase in atmospheric carbon dioxide levels. Additionally, deforestation reduces the number of plants absorbing the gas.

    Carbonate ions are an important building block of structures such as seashells, coral and planktons. The lack of carbonates may reduce the ability of calcifying organisms to form their shells and skeletons, and existing shells may begin to dissolve.

    Over time, ocean acidification will cause coral reefs, a key habitat for fish, to break down rapidly and affect organisms with a calcium carbonate exoskeleton or shell, including sea urchins, sea snails, clams and oysters. This will have adverse impacts on the health of the marine ecosystem. 

    Our oceans play an essential role in keeping the Earth’s carbon cycle in equilibrium. Let’s start today and do your part in protecting the ocean by reducing your carbon footprint.


    Want to do more beach themed activities? Order your Squizzel box now and let the adventure begin!