Most of us with a bath will make or use bath bombs. They are great fun and can add to the experience of bath time.
We know that as soon as we add bath bombs to water, they ‘activate’ so what does this actually mean?
An absolutely basic bath bomb fizzer can be made with just two ingredients, Sodium bicarbonate (Bicarb) and Citric Acid with a little binding agent that will evaporate as they dry. Providing they don’t get wet or draw moisture from the surrounding air, they’ll happily remain as solid chunks until they get thrown in the bath.
When it comes to bath bombs, water is known as a catalyst for a chemical reaction that will occur between the bicarb and citric acid. That just means it is necessary as, in their dry state, this reaction will not occur.
When they are added to the bath, the molecules within the bicarb which has an alkaline pH and the citric which has an acid pH combine to neutralise each other and create the gas carbon dioxide. This carbon dioxide can be seen in the bubbles erupting from a bath bomb that helps whizz them around the bath or make them spin. The neutralisation process as other molecules mix also creates water and sodium citrate which is a salt. The creation of this salt is what many people believe helps soften water slightly.
Of course, there are plenty of other ingredients that can be added where we believe they have a purpose such as colourants, scent, surfactants for foam, clays or starches to help harden bath bombs so testing is really important.
Bath bombs are pretty clever things.
