Acids and bases, when mixed together, create a chemical reaction. During this chemical reaction the atoms rearrange and create new substances. a. What has to be true about the substances before and after the reaction if the reaction took place in a closed system?

b. What states why that has to be true?

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

i believe the answer is three water molecules