Mystery #2Tier 2gases / particles
Why does a blown-up balloon slowly go soft and shrink after a few days?
You blow up a balloon, tie it tight, and it is fat and firm. Come back a few days later and it has gone soft and wrinkly, smaller than before. It never popped, and you cannot hear it hissing anywhere. So where has all the air gone?
Your guess
What do you reckon is happening to the air inside the balloon?
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