Trends in the formulae of oxides and hydrides

What are the formulae of the highest normal oxides of the elements of the third Period  

If we allow expansion of the octet, this valency pattern occurs because in its highest oxide, each element uses all its outer electrons in forming bonds. Thus, with six outer electrons, sulfur can form six electron-pair covalent bonds, and an oxide SO3 results. In the case of the hydrides the pattern is different. There is no expansion of the octet, and the elements attain noble gas configurations in the hydrides. This gives formulae AH , where jc takes values 1, 2, 3, 4, 3, 2, 1,0 across a row. 

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