Science Friday

Not an original idea, but I am back dating a post for Friday (post being typed on Sunday); we raced out of hear for camping shortly after finishing Thing One's science lesson. One of the lessons is entitled "Science: Chemistry - Bananas and Oxidation". You know those fruit (and some vegetables) that turn brown shortly after being peeled: bananas, apples, and potatoes for example. It's a chemical reaction to air when the white flesh is exposed to air. Here's what was done and observations made:

A banana, not exposed to air yet. Should be banana white,
except for a bruise maybe.

Just sliced to allow for more oxidation.

About 35 minutes later, the first signs of the banana slices
turning brown. This took a bit longer than was anticipated.

Approximately 20 minutes later, the slices
are darker brown.

Just over three hours later, a skin is forming over
the slices. These where left out until Saturday evening.
They weren't much darker before being dumped into
the compost.

Next time we try this, we'll have put lemon juice on some of
the slices. Citrus fruits have an acid in them that make oxidation
slow down. It would have been interesting to note the difference
between the two groups.