On Tuesday afternoon, we did two very fun and interesting science experiments. They were to do with density. We had to do it outside, because the experiments were very messy!

For the first experiment, we filled a test tube three quarters full of olive oil, the last quarter was filled with water. Immediately the oil and water separated. The oil all went to the top of the tube, and the water all went to the bottom of the tube. This was because the oil was denser than the water.

Next, we broke up a vitamin c tablet into eight pieces and put the pieces one by one into the tube. The first piece of tablet caused the oil and water to bubble and froth. The oil kept its original colour, but the  water turned dark yellow.

When we added another piece of tablet, the water turned very pale orange. We took off the lid of the test tube and saw little orange bubbles appearing at the surface. They looked like algae. Then the mixture bubbled over the top of the tube, so we put the lid back on.

Then we left it for a while, and then we shook it. We opened the lid, but it exploded everywhere, so we shut it again.

After that, we added the rest of the vitamin c tablet, and the water turned neon orange. Then we opened it again, and white foam exploded out, in little yellow bubbles.

Eventually, we poured out the mixture, and the oil separated from the water and the dissolved tablets.

For the second experiment we filled a tray with water, and added some drops of oil with a pipette. We had a selection of materials to try to take the oil out. The materials were straw, cotton wool, sawdust, shredded paper, blue roll and a newspaper. We discovered to our surprise that the straw was most efficient, getting rid of almost all of the oil in a very short space of time. The next best was cotton wool, which was very efficient, but took quite long.

We enjoyed these experiments, and they were very informative and made us think.