Homework Problem #3

[805377003]

Can someone explain how to do this problem?

The formulas of the bromate ion, BrO−3, and chlorate ion, ClO−3, are very similar. However, the formulas of the nitrate ion and phosphate ion contain different numbers of oxygen atoms. This is also true for the formulas of the nitrite ion and phosphite ion. Draw the Lewis structures of the nitrite, nitrate, phosphite, and phosphate ions. Draw the structures that minimize formal charges, and be sure to include the appropriate formal charges and lone‑pair electrons.

[Audra Mcleod 3G]

Hello!
In this problem, you have to draw the lewis structures of nitrite (NO2-), nitrate (NO3-), phosphite (PO3 -3), and phosphate (PO4 -3), but the main focus is to draw the structure that minimizes the formal charge. This would involve using double bonds between the central atoms and oxygen atoms when possible to achieve a formal charge of 0, but also ensuring that the total charge on your structure still amounts to the net charge on the ion. Also, keep in mind the possibility of an expanded octet with the P atom.

[Marisa Gaitan 2D]

I agree with the post above, making sure to minimize formal charge and that the formal charges added up match the overall charge of the compound. Also, it is important to note that some elements such as phosphorous can have an expanded octet, meaning they can take on more that 8 valence electrons, that helped me when drawing these structures!