Make an erupting vinegar and bicarb volcano

Erupting papier mache volcano using vinegar and bicarbonate of soda

 

This is a fantastically dramatic science experiment to try at home.

We’ve created instructions to help you build your own papier-mâché volcano which looks great but does take some time. You may choose to jump straight ahead to the chemical reaction!

 

To make the volcano you will need:

  • An empty cup, jar or small bottle
  • An easily cleanable tray
  • Sticky tape
  • Newspaper or scrap paper
  • PVA glue
  • Paintbrush
  • Paint

 

Construct the papier-mâché volcano

1. Place your cup in the middle of the tray and use sticky tape to attach it firmly.

Attaching plastic cup to tray for crater of the volcano


2. Scrunch small pieces of paper into balls and arrange them around the cup to make the basic shape of a volcano. Use loops of sticky tape to attach the balls to the cup and each other.

Scrunched paper balls surrounding the cup to make the body of the volcano


3. Tear strips of paper and lay them over the volcano shape, using generous amounts of PVA glue to stick them down. Work methodically to cover the whole structure, overlapping the strips of paper.

Papier mache body of a volcano with a cup at the centre


4. Leave the volcano to dry.


5. Paint the volcano according to your own design. You may need to do a couple of layers of paint, leaving time for it to dry in between.

Painted papier mache volcano

     

    To create the chemical reaction you will need:

    • 50ml vinegar
    • 1 tbsp washing up liquid
    • 2 tbsp water
    • Red food colouring (optional)
    • 1 tbsp bicarbonate of soda

     

    Prepare the chemical reaction

    1. Mix the vinegar, washing up liquid, water and red food colouring (if you’re using it) in a jug.

    2. Place the bicarbonate of soda in the bottom of the cup at the centre of your volcano and ensure you're working in a well ventilated room, or even better outside!

    3. Pour the vinegar mix into the cup, stand back and watch what happens!

      Preparing to pour the vinegar mix into the centre of the volcano

       

       

      What is happening as the volcano erupts?

      Bicarbonate of soda is an alkaline, whilst vinegar is an acid. When the two combine a chemical reaction occurs which produces carbon dioxide gas.

      This gas then gathers around the washing up liquid creating even bigger bubbles. As this happens pressure builds within the cup until the “lava” overflows the top, just like a real volcano!