I did an experiment with my kid. We put vinegar and baking powder in a bottle and the balloon inflated. Which I expected. The balloon went down. Which I expected.
The reaction is endothermic so absorbs the heat whilst reacting. Therefore it ultimately shrinks back and will be colder. Get the thermometer out and add another aspect to the experiment.
Why has the balloon gone inside the bottle?
I did an experiment with my kid. We put vinegar and baking powder in a bottle and the balloon inflated. Which I expected. The balloon went down. Which I expected.
But now a vacuum has been created.
How come?