Group 6A 16 The Oxygen Family

Phosphorus forms two important oxides, P4O6 and P4O10. Tetraphosphorus hexa-oxide, P4O6, forms when white phosphorus, P4, reacts with limited oxygen  

Despite the formula, H3PO3 has only two acidic H atoms the third is bonded to the central P. It is a weak acid in water but reacts completely with strong base  

Salts of phosphorous acid contain the phosphite ion, HP03 .  

Commonly known as phosphorus pentoxide from the empirical formula (P2O5), tetraphosphorus decaoxide, P4O10, forms when P4 burns in excess O2  

The presence of many H bonds makes pure H3PO4 syrupy, more than 75 times as viscous as water. H3PO4 is a weak triprotic acid in water, it loses one proton  

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Oxygen (O) and sulfur (S) are among the most important elements in industry, the environment, and organisms. Selenium (Se), tellurium (Te), radioactive polonium (Po), and newly synthesized element 116 lie beneath them in Group 6A(16) [Family Portrait, p. 444]. 

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