What you'll need:

•Small soft drink bottle
•Water
•Food colouring
•2 tablespoons of cooking oil Instructions:

1.Add a few drops of food colouring to the water.
2.Pour about 2 tablespoons of the coloured water along with the 2 tablespoons of cooking oil into the small soft drink bottle.
3.Screw the lid on tight and shake the bottle as hard as you can.
4.Put the bottle back down and have a look, it may have seemed as though the liquids were mixing together but the oil will float back to the top.
What's happening?

While water often mixes with other liquids to form solutions, oil and water does not. Water molecules are strongly attracted to each other, this is the same for oil, because they are more attracted to their own molecules they just don't mix together. They separate and the oil floats above the water because it has a lower density.

If you really think oil and water belong together then try adding some dish washing liquid or detergent. Detergent is attracted to both water and oil helping them all join together and form something called an emulsion. This is extra handy when washing those greasy dishes, the detergent takes the oil and grime off the plates and into the water.

Cut Ice Cubes in Half Like Magic

What you'll need:

•One ice cube
•A piece of fishing line (or something similar) with a weight tied to each end
•A container
•Some kind of tray to keep things from getting wet
Instructions:

1.Turn the container upside down and put it on the tray.
2.Place the ice cube on top of the upside down container.
3.Rest the fishing line over the ice cube so that the weights are left dangling over the side of the container.
4.Watch it for around 5 minutes.
What's happening?

The pressure from the two weights pulls the string through the ice cube by melting the ice directly under the fishing line. This is similar to ice skating where the blades of a skater melt the ice directly underneath, allowing the skater to move smoothly on a thin layer of water.