After you slam down your next fizzy drink, stop and think before you throw the plastic bottle in the nearest recycling bin. I’m not trying to encourage you to be environmentally irresponsible, I just want you to try an experiment with the bottle! You’ll be able to recycle it later.
Before we get stuck into the experiment, you might be interested to know that many plastic bottles are made from a plastic called polyethylene terephthalate. Try getting your lips around that! Fortunately, it’s much easier getting them around an actual bottle. Due to its complicated name, this plastic has been given a much simpler nickname – PET. Bottles made from this type of plastic are known as PET bottles.
PET bottles were developed in the mid 1970’s by the America inventor Nathaniel Wyeth. He wanted to create something to replace glass bottles, which were heavy and broke easily. Nathaniel’s first few bottle manufacturing attempts resulted in some rather misshapen and odd looking hollow lumps of plastic. Eventually, however, Nathaniel created the perfect plastic PET bottle – as well as the beginning of an enormous worldwide environmental problem.
Australians consume just over 80,000 tonnes of PET every year. Only 61 per cent of this plastic is recycled. PET bottles can be recycled to make a huge range of products including: filling for sleeping bags and pillows, carpet fibre, large plastic sheets, shoe laces and even clothes!
Plus, you can use them for scientific experiments!
WHAT YOU NEED:
• 2 large PET bottles
• nail
• hammer
• balloons
• a good friend!
WHAT TO DO:
1. Use the hammer and nail (and an adult’s help) to punch a hole in the bottom of one PET bottle.
2. Push a balloon into each bottle and then stretch the lip of each balloon over the opening of each bottle (see diagram).
3. Give the bottle without the hole to your friend, keeping the other bottle for yourself (don’t let your friend know that your bottle has a hole in it!).
4. Challenge your friend to a competition. The first person to blow up their balloon in the bottle wins.
5. Ready, set, BLOW!
Your friend won’t be able to blow up their balloon, but you will!
When you blow up your balloon, you push all the air inside the bottle out through the hole in the bottom of the bottle. However, when your friend tries to blow up their balloon, there’s nowhere for the air to go. As a result, they wind up trying to squash the air in the bottle into a smaller space – something that their lungs aren’t powerful enough to do.
Don’t let your friend try too hard to blow up their balloon or they’ll pass out or bust a lung! Let them in on the secret so that they can try the experiment on someone else.
