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Amazing atoms
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If you could keep smashing
an object into smaller and
smaller bits, you would
eventually break it down
into bits that can’t get any
smaller – atoms. Atoms are
tiny particles that make up
everything around us.
Inside an atom
Inside an atom are three tiny types
of particle: protons, neutrons, and
electrons. Protons and neutrons
make up the atom’s nucleus (core).
The electrons are outside this.
Golden number
The number of protons
in an atom is called its
atomic number. The
atomic number of
gold is 79. This
means that each
gold atom has
79 protons.
How many atoms are there in a drop of water?
Science and technology
Molecules
Substances are made from
little groups of atoms called
molecules. The molecules in
water have three atoms.
A water molecule has
two hydrogen atoms
and one oxygen atom.
Hydrogen atom
Hydrogen atom
Oxygen atom
GOLD
Au
79
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