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ELI5 Yahaaa

One kind of atom, all the way through

Why Is There a Table of Everything?

An element is a substance made of only one kind of atom, and there are only 118 of them known.

O 8 One kind of atom onlyA number saying howmanyA short name — O, Fe,Au118 known, about 90found in nature
Every tile on the table is one kind of atom.
  1. Step 1 of 5

    An element cannot be split into anything simpler.

    Gold — an element One kind of atomthroughoutWater — a compound Two kinds, joinedtogether

    Gold is gold all the way down — cut it as small as you like and every piece is still gold atoms. There is no recipe for gold, because it is not made of anything else.

  2. Step 2 of 5

    There are 118, and about 90 turn up in nature.

    Found in natureOnly ever made in alaboratory

    The rest have only ever been made a few atoms at a time in laboratories, and most vanish again within seconds.

  3. Step 3 of 5

    They were lined up because they repeat.

    1 O 8 Sort them byweight2 Noticebehaviourrepeating3 Start a new roweach repeat

    Sort the elements by size and their behaviour comes round again and again. Start a new row each time the pattern restarts and the similar ones stack into columns.

  4. Step 4 of 5

    A column is a family.

    Left edge — fizzviolently in watersodium,potassiumMiddle — the everydaymetalsiron, copper,zincRight edge — refuse toreact at allhelium, neon,argon

    The far-left column are soft metals that fizz in water. The far-right column are gases so unbothered that they will not react with anything at all.

  5. Step 5 of 5

    You are made of surprisingly few of them.

    Oxygen65% of you,mostly as waterCarbon18%Hydrogen10%Everything elsethe other 88elements

    Just four elements — oxygen, carbon, hydrogen and nitrogen — make up about 96% of your body. The other ninety are the last few percent.

    Hydrogen alone is about 90% of every atom in the universe. The table is long, but nearly all of space is the first tile on it.

The short version

An element is a substance made of a single kind of atom, and the periodic table lines them up so the families fall into columns.

Try it yourself

Look at the little symbols on a vitamin packet — Fe, Zn, Ca. Each one is a tile from the table, and your body genuinely needs a pinch of it.

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