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Hi, I'm Matthew. Today on Experiment Time, we're going to compare oxidation in different fruits.

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Have you ever noticed a fruit that's turned brown? Or have you ever made a fruit salad and seen what

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happens to the fruit after you slice it? Hmm, what's happening? We're going to compare different

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fruits I've chosen an apple an orange a banana and also an avocado we also need

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a plate for each fruit and a knife cut fruit turns brown because of oxidation

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when the soft interior part of the fruit is exposed to air its electrons are lost

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The oxygen in the air gains electrons from the fruits atoms. This is a chemical

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change. But which fruit do you think will oxidize the most? Which fruit will

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oxidize the least? Think about it and then write a hypothesis. Now we cut the

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fruit in half carefully with the knife. Now we put each fruit on a plate and

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observe it carefully wait 10 minutes do this three times so you can see the

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oxidation process develop while you're waiting you can draw a results table the

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banana has started to go brown and the Apple as well the avocado still looks

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fresh. And the orange? The orange is still fresh as well. Write down what you

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reserve in the table. If you have a camera you can use it to take photos at

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each stage. Now let's wait ten more minutes. We can see the fruits are still

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oxidizing. The banana and the apple are darker than before. The avocado is

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starting to turn brown around the edges and the orange still hasn't changed record your results

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on a table and take a photo right so half an hour has passed since we cut the fruit

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i can certainly see the difference when you have recorded your results you can start to analyze

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them what changes in appearance do you observe how long did it take each fruit to change

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Which fruits didn't change at all? Was your hypothesis correct? Why do you think the orange

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didn't go brown like the other fruits? That's right, it's a citrus fruit and the citric acid

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slows down the oxidation process. How can you use this information to help you preserve fruit?

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That's right, squeeze a bit of orange juice or lemon juice on your sliced fruits and they won't go brown

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Great, you try, choose your own fruits

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See you later alligator