Select all ionic compounds in which the number of anions present is two.

carbon dioxide
X manganese(II) hydroxide
mercury(II) carbonate
X mercury(II) phosphate
ammonia
sulfur dioxide

Hello,
I know manganese(II) hydroxide mercury(II) phosphate both have two anions, however I am unsure about carbon dioxide and sulfur dioxide. would the oxygens in both cases be considered the anion or am I completely off base with this?
Thank you!

2 answers

its just the 2nd and 4th one
CO2 is a molecule. SO2 is a molecule. NH3 is a molecule. In the first place, these are not ionic compounds and there is no way to consider the O in CO3 or SO2 or the H in NH3 to be anions. You picked two of the three ionic compounds there. The other compound, HgCO3, although we might consider it to be ionic, the # anions is not two.