Our Potions Masterclass required the children to apply  both their chemistry and maths thinking in two experiments.

Polyjuice Potion:

Everyone needed to measure out the correct capacity of liquids and add just the right amount of powder to create a bubbling, effervescent  experiment in our  mini cauldrons.

• 25ml of Dragon’s Tears (distilled vinegar)
• 25ml of Elixir of Life (water)
• 1 heaped tsp of Powdered Pixie (bicarbonate of soda)

P 1-4 used 25ml cylinders to measure the liquid ingredients. P 4- 7 had an extra challenge of working with different capacity scaled cylinders to add the correct quantities. It was very entertaining watching the cauldrons foam and bubble over.

We chatted about how combining the vinegar (an acid) with the baking soda (a base) results in an entirely new substance – carbon dioxide gas.  As this gas quickly forms it creates bubbles.

Levitating Bat Droppings:

To conduct this magical, visual trick, the children had to add bat droppings (small raisins) to Frog’s Urine (lemonade) in a glass.  They then had to chant Wingardium Leviosa and watch the droppings rise and fall repeatedly.

We had an interesting discussion  as to the cause of this phenomenon.  We learned that carbon dioxide gas bubbles in the lemonade attach themselves to the body of the raisin. They act as swimming arm bands, raising the raisin to the surface of the liquid. Once the bubbles burst at the surface of the glass, the raisin sink until new bubbles form on it’s surface area and the process repeats.

Successful Learners