Ions are Formed when atoms lose or gain electrons in order to fulfill the octet rule and have full outer valence electron shells.
They cancel each other out so they are neutral.
The correct definition of density is the degree of compactness of a substance.
The density of CO2 getting from experiment is 0.1/0.056 = 1.79 g/L. The percent error of this is (1.96 -1.79)/1.96*100%=8.67%. So the approximate percent error is 8.67%.
