Science week at Fusion
Fizzy lemon- The sodium bicarbonate of the baking soda reacts with the citric acid in lemon juice to form carbon dioxide gas. The gas bubbles are trapped by the dishwashing soap, forming fizzy bubbles.
Fireworks in a jar – this was cool to watch, we used oil, water, food colouring.
It’s to do with the density of each liquid. The food colouring will dissolve into the water, but the oil won’t. By mixing the oil and food colouring together first, you slow the mixing process that would normally happen with the water and the food colouring. The food colouring drops down into the water (because it is denser than the oil) while the oil stays on top of the water (water is also denser than oil). When the food colouring eventually starts to mix with the water, it creates a tiny explosion, like a firework.