Question

Atoms of different elements are different sizes. Explain why the size of atoms does not increase smoothly as you progress the Periodic Table within a single period from left to right, even though the atomic number increases as you do so.

Answer 1

The answer I gave here should help you with your question:
http://openstudy.com/study#/updates/50ee2a93e4b0d4a537cd804b

Answer 2

Im still kinda lost.. :/

Answer 3

As the atomic mass increases, so does the atomic size DOWN THE GROUPS but NOT across the periods. Atom size decreases from left to right (getting smaller) because as the atomic mass increases, so do the nuclear forces that hold the atom together, thus making the atom want to become more dense and decrease its size from left to right across the periodic table.

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