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Name: craig e tanner
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 

In the periodic table, what is the difference between the columns labled "A" and "B"?

As a short the columns labeled 'A' are called the "main-group elements," and all have valence-shell configurations ns^a np^b (a and/or b could be 0 for some compounds). The columns labeled 'B' are the transition metals, and their valence-shell configurations involve d orbitals.

Now please don't ask why one is called A and the other B.... I Just Don't Know.


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