We did lots of fun and interesting things during Science Week. We all agreed that our favourite experiment was when we made Lava Lamps.
We poured water into an empty bottle and then we pour oil in on top. The oil floated to the top of the water. We then added food colouring which only mixed with with the water. Next we added an effervescent tablet and we watched something exciting happen!
We learned that the oil floated on top of the water because it is less dense or lighter than water. The food colouring has the same density as the water so it sinks through the oil and mixed with the water. When you add the tablet it sinks to the bottom and starts to dissolve. As it dissolves it makes gas, carbon dioxide. Gas or air is lighter than water si it floats to the top. The air bubbles bring some coloured water with them to the top. When the air comes out of the coloured water blob, the water gets heavy again and sinks. It does this over and over again until the tablet is fully dissolved.
