Children may ask why did the lava lamp erupted? Introduce children to science principles such as chemical reactions – A chemical reaction occurs when vinegar and baking soda are mixed. When this happens a gas called carbon dioxide is made and does not have enough space in the container, so it tries to escape, causing the eruption! Ask the children what they think will happen when more vinegar than baking soda is used (vice versa). Jot down their hypothesis and then test to see what happens.