DEMONSTRATION II:  Lighter and heavier atoms

There are 92 different kinds of atoms that make our world, and each has a different weight.  The lightest, Hydrogen, is a gas that floats because it’s lighter even than air.  Bismuth and Lead are some of the heaviest kinds of atoms, and you can feel that when you hold them in your hand.  What about Silicon?  Is it lighter or heavier?

Demo I:  Air is matter