Write the formula for these compounds:
a) potassium sulfide
b) iodine heptafluride
Hello and thank you for using BrainMass!
Sulfide is a a combination of Sulfur atom(s) with oxidation number -2 with other elements.
Potassium is an alkali metal with one electron in the outer shell, Thus it has an oxidation number +1 (it is very happy to donate this electron)
To balance the compound (having total oxidation number 0) we need one sulfur (-2) and two potassiums (+1)
Thus (underscore denotes a subscript):
potassium sulfide is K_2S (metal first).
Iodine and Fluor are ...
Solution includes explanation and chemical formula. 285 words.