Ages 2+

Blobs in a Bottle

Create your own blobs in a bottle science experiment

Your children will love exploring coloured water and oil and a surprise element will make this science experiment even more exciting.

It’s always a hit with children!


Things you will need

  •  A clear plastic bottle, try and use one with smooth sides.
  • Water
  • Baby oil (or you could use vegetable oil instead)
  • Alka Seltzer tablets
  • Food colouring
  • Funnel.


How to Do It

  • Fill the bottle approximately one quarter with water
  • Pour the baby oil or vegetable oil in the bottle until it is almost full. It might be helpful to use a funnel and you may have to wait a few minutes for the oil and water to separate before commencing the next step. This is an opportunity to count the seconds with your child as you wait to see the ingredients separate
  • Add a few drops of some food colouring and watch as the colour sinks through the oil
  • Take time to explore this step and to talk and wonder with you child about what is happening
  • Break the Alka Seltzer in half and drop part of it into the bottle
  • The magic then begins! This step can be repeated again and again.


What Learning is Occurring?

  • Science concepts – Cause and effect (through investigating and exploration)
  • Encouraging children to develop patience and understand fairness in turn taking
  • Problem solving skills – Exploring ideas and concepts, clarify and challenge thinking, negotiate with others to complete a task and share new understanding
  • Maintain respectful and trusting relationships with familiar adults as they explore something new
  • Through science experiences children learn to investigate, imagine and explore ideas
  • Reflective thinking – children consider why something happens, what their role is in making change and what can be learnt from these experiences
  • Children confidently contribute their ideas and build on knowledge.


Tips and further experiments

  •  Explore what happens if you put the lid on after dropping the Alka Seltzer into the bottle? Use some of your other senses to find out (listen, feel etc.)
  • Explore what will happen if you put a whole Alka Seltzer in the bottle. How is this different?
  • When it stops bubbling, try sprinkling some salt into the lava lamp. What does the salt do?


Age Considerations

  •  For younger children

As we are using Alka Seltzer tablets, we need to ensure his part of the experiment is supervised and that we are breaking the pieces for them and handing them piece by piece as they put the Alka Seltzer into the bottle with adult supervision, some of the younger children may need assistance with this and also pouring the water and baby oil/vegetable oil.

  • For older children

As we are using Alka Seltzer tablets, older children will still need to be supervised but are able to break the Alka Seltzer into pieces with adult supervision.

  • Make sure the Alka Seltzer tablets are put away safely after the experiment.
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From Kristina Solomon – Assistant Manager at Guardian Tempe

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