Showing posts with label Science. Show all posts
Showing posts with label Science. Show all posts
Aug 7, 2011
Making Crystals
How exciting! Today we talked all about crystals and what they are like. We are being real scientists and having a go at making crystals using hot water, salt or sugar. Here are some photos of our experiments today - we will keep you updated with photos as they change!
Jun 29, 2011
Jun 28, 2011
Jun 22, 2011
Jun 21, 2011
How to Make Ice Cream!
What you'll need:
2 tablespoon sugar
1 cup milk or half & half
1/2 teaspoon vanilla
8 tablespoons rock salt
1 large plastic food storage bag (e.g., Ziploc)
1 small plastic food storage bag
Ice cubes
How to make it:
Fill the large bag half full of ice, and add the rock salt. Seal the bag.
Put milk, vanilla, and sugar into the small bag, and seal it.
Place the small bag inside the large one, and seal it again carefully.
Shake until the mixture is ice cream, which takes about 5 minutes.
Wipe off the top of the small bag, then open it carefully. Enjoy!
Why does this happen?
Ice has to absorb energy in order to melt, changing the phase of water from a solid to a liquid. When you use ice to cool the ingredients for ice cream, the energy is absorbed from the ingredients and from the outside environment (like your hands, if you are holding the baggie of ice!). When you add salt to the ice, it lowers the freezing point of the ice, so even more energy has to be absorbed from the environment in order for the ice to melt. This makes the ice colder than it was before, which is how your ice cream freezes. Ideally, you would make your ice cream using 'ice cream salt', which is just salt sold as large crystals instead of the small crystals you see in table salt. The larger crystals take more time to dissolve in the water around the ice, which allows for even cooling of the ice cream.
Have a look at this video that compares a normal melting ice cube with an ice cube that has salt sprinkled on it. Which melts faster?
2 tablespoon sugar
1 cup milk or half & half
1/2 teaspoon vanilla
8 tablespoons rock salt
1 large plastic food storage bag (e.g., Ziploc)
1 small plastic food storage bag
Ice cubes
How to make it:
Fill the large bag half full of ice, and add the rock salt. Seal the bag.
Put milk, vanilla, and sugar into the small bag, and seal it.
Place the small bag inside the large one, and seal it again carefully.
Shake until the mixture is ice cream, which takes about 5 minutes.
Wipe off the top of the small bag, then open it carefully. Enjoy!
Why does this happen?
Ice has to absorb energy in order to melt, changing the phase of water from a solid to a liquid. When you use ice to cool the ingredients for ice cream, the energy is absorbed from the ingredients and from the outside environment (like your hands, if you are holding the baggie of ice!). When you add salt to the ice, it lowers the freezing point of the ice, so even more energy has to be absorbed from the environment in order for the ice to melt. This makes the ice colder than it was before, which is how your ice cream freezes. Ideally, you would make your ice cream using 'ice cream salt', which is just salt sold as large crystals instead of the small crystals you see in table salt. The larger crystals take more time to dissolve in the water around the ice, which allows for even cooling of the ice cream.
Have a look at this video that compares a normal melting ice cube with an ice cube that has salt sprinkled on it. Which melts faster?
Jun 20, 2011
Jun 19, 2011
Apr 9, 2011
Apr 7, 2011
Science Day Video's
As we went through our science experiments in our groups we recorded our experiments using iMovie. Lots of us had never used iMovie so we were learning lots! We learnt how to record ourselves in iMovie and how to add in text for credits (credits tell people about who was in the movie and other jobs!).
In the afternoon we watched our movies and were very impressed with our hardwork. We know there are things that we can improve on but for our first movies - we think they are superb!
We wanted to share them with our blog audience - so have a look!
Apr 6, 2011
Feb 15, 2011
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