posted by Melissa .
Write the chemical formulas for the compounds containing each of the following: a) one calcium atom for every two iodide atoms. b) two nitrogen atoms for every four oxygen atoms. c) one silicon atom for every two oxygen atoms. d) one zinc atom for every two chlorine atoms
What are you having trouble with? The question tells you how the atoms are combined. For example,
a is CaI2.
b is N2O4.