Archive for June, 2013

Magnets and Sugar – Heterogeneous Mixture

While making salt and water a mixture to float eggs in was fun, it can be another experiment to separate the salt from the water. This can be done using a process of evaporation and distillation.The mixture is a homogenous one and requires considerable effort to separate it in to its components.

In this experiment here we look at a more heterogeneous mixture.The components of the mixture are sugar and iron filings. Half cup of granular sugar mixed with half cup of iron filings make a good mixture that would seem difficult to separate if one was not aware of the unique property of iron.

Iron is attracted by magnets.  If we stir a magnet into the cup that holds this mixture of sugar and iron filings all the iron will begin to stick to the magnet and will be easily separated from the sugar. In this science experiment we use the principle of magnetism to separate the mixture.

In general the homogeneous mixtures are more difficult to separate and require more effort than a heterogeneous mixture does. Come up with a list of different mixtures and classify them as either homogeneous or heterogeneous. Then add details on how you can separate the mixture into its individual components.

Leave a Comment

Science Experiments with Salt

In the last two experiments with ice I asked you to use salt to melt the ice faster to help with the artistic process. Salt lowers the freezing point of water so the ice at room temperature begins to melt faster. Here’s a simple experiment to help prove that this actually happens.

Take two identical cups of Styrofoam and add half cup water to them. Now in one of them also add a big spoon of salt. Stir it in and place both cups in the freezer for 15 minutes. When you take them out at the end of that time period it will be easy to see that the cup with plain water is ready to form ice and is crystallizing well while the other one with salt is still liquid.

The salt has lowered the freezing point and it will be a while more before the salt water is ready to freeze. Another fun experiment is to make things float using salt in the water. This is sort of like the reason why no one can sink in the Dead Sea. Use an object that floats easily like a plastic spoon and one which usually sinks like an egg.

Now while the plastic spoon will float in plain water, the egg will need close to 100gm of salt being added to the water before it begins to float. Calculate how much salt is needed to make other things like a coin, or an eraser float in a science project.

Leave a Comment

Making Colorful Ice Sculptures

We have all seen and admired ice sculptures by artists. Making colorful Ice Sculptures is not just for the professionals. In this heat a great way to cool off is to play with ice sculptures. Here is how you can set up a whole afternoon of fun with absolutely no expense.

Ice sculptures need huge hunks of ice as raw material so use any big bottle, vessel or even balloons to fill up with water and freeze. The more ice you have available at hand the more fun can be had by all. You may also like to use colors to make the sculptures more interesting.

You can use basic liquid food colors from the kitchen or you can add some tempera colors to the ice while it sets. Do a little of both to make the science project more interesting. Once you have the ice blocks ready use different methods to shape it. You can use a knife to chip it, or use ice to melt bits of it in a hurry.

Add the liquid colors in blotches or as sprinkles to make the ice sculptures look more cheerful. This is a science project where your creativity can be given full reign. Enjoy the different looks before they all melt!

Leave a Comment

Painting with Ice Cubes

No one in their right minds would confuse crayons with ice cubes, so how does this science project work? Quite simply actually! What you need to do is take an ice cube tray and add a teaspoon of tempera paint to it. Next add some water and mix up the paint with the water.

Keep it standing for a few minutes and then mix it up again before you put it into the freezer. Stick in a toothpick in the ice cubes for easy handling. Don’t worry if you forget to add the tooth picks. It will just mean slightly messy hands, but the paint washes right off with soap and water.

Once the colored ice cubes are set remove them from the ice tray and use them on a thick paper to paint out whatever design you fancy. Run them in circles or triangles to form multi layered designs. You could also just leave them in strategic spots on the paper and allow them to melt into one huge abstract design.

Want to speed up the melting of the paint filled ice cubes? Just sprinkle some salt on them. You have used basic science like freezing, mixing fluids, and using a catalyst to speed up melting of ice. Pretty cool for a home grown science project!

Leave a Comment

How Magician’s Affect Perception to do Magic

If you have been to a magic show and wondered with open mouth astonishment about just how the magician pulled that trick off, I’ve news for you. There is no magic which is not based on science and scientific principles. Most of their spectacular events deal with merely tricking you into believing that something has happened, when in fact it has not.

Perception is the sense we make of the world around us based on the stimulus received from our sense organs. In case of the magician, our eyes perceive seeing something based on the raw stimulus the magician provides, but very often this perception is false.  The raw stimulus is manipulated by the magician in such a manner that what we think we see is not what actually is happening.

Take for instance the three card trick where the queen is shuffled along with two other ordinary cards. We think we have marked the position of the queen before the magician begins shifting the locations of the cards and follow that card well enough. However what we do not realize is that before the magician began shuffling he had already changed the location of the queen facing downwards.

So no matter how well we follow the card we are always looking at the wrong one and will never point at the queen when he asks us to. The concept of what we perceive and how we perceive things have been the subjects of major scientific research over the years. However it is the magicians who have made best use of this principle to entertain and amaze us.


Leave a Comment