Un-mixing Milk

This week we tried 2 different ways to "un-mix" milk. The first way involved brute strength! We poured some heavy cream into a jar, and we shook it and shook it until it separated into a clear liquid and a creamy solid, better known as butter.  The second way we extracted solids from the milk was through a few chemical reactions. First we added some vinegar to the milk to curdle it. Then we separated the solid proteins using filter paper, and neutralized any extra vinegar with baking soda.  Finally we added a little water, resulting in our own home-made glue.  

General Science: White powders

This week we continued our exploration of physical and chemical properties by investigating 4 different white powders: sugar, salt, corn starch, and baking soda. The physical properties we investigated included: how each one looks under the microscope and how each one feels. As for chemical properties, we combined the powders with vinegar and iodine and recorded the results. Finally we looked at whether any of the powders conduct electricity when dissolved in water.

The kids now have a comprehensive data sheet on these substances and their physical and chemical properties. If by chance, they should come into contact with some unknown white powder, making an identification should be a piece of cake!

One never knows when these skills and/or data might come in handy...

General Science: It's a Gas!

For our experiment this week, we did an oldie but a goodie...what happens when you mix baking soda and vinegar?

Having some experience with making volcanoes or otherwise messing around in the kitchen, the kids guessed correctly that the combination would produce, in their words, "AN EXPLOSION!!!" (Aren't you glad this happens at my house and not yours?!)

This week we took it one step further to show that the combination of baking soda and vinegar produces a gas that can put out a fire. Passing a lit candle over baking soda had no effect on the flame. Same deal for the vinegar, but when you combine the two, and you get your EXPLOSION (i.e. bubbles), passing the candle over extinguishes the flame. Why does this happen? Mixing baking soda and vinegar is a chemical reaction, and as such, produces something new, carbon dioxide. That's what the bubbles are, and they have the property of putting out a fire and that's why they carbon dioxide in an actual fire extinguishers. Cool, huh!?

General Science: It's a gas!

For our experiment this week, we did an oldie but a goodie...
what happens when you mix baking soda and vinegar?

Having some experience with making volcanoes or otherwise messing around in the kitchen, the kids guessed correctly that the combination would produce, in their words, "AN EXPLOSION!!!" (Aren't you glad this happens at my house and not yours?!)

This week we took it one step further to show that the combination of baking soda and vinegar produces a gas that can put out a fire. Passing a lit candle over baking soda had no effect on the flame. Same deal for the vinegar, but when you combine the two, and you get your EXPLOSION (i.e. bubbles), passing the candle over extinguishes the flame. Why does this happen? Mixing baking soda and vinegar is a chemical reaction, and as such, produces something new, carbon dioxide. That's what the bubbles are, and they have the property of putting out a fire and that's why they carbon dioxide in an actual fire extinguishers. Cool, huh!?