Which substances have the same empirical formula as each other and why?

Harvey mixes two liquids. which observation of the new mixture most likely indicates a precipitate is forming?

Darla claims that the first periodic table developed by mendeleev was not completely accurate, so it is not useful at all. harmony argues that it establish the periodic table we use today, making it more credible. who is correct and why? darla is correct, because a model that has any mistakes should be thrown out. darla is correct, because a good model would not need to change. harmony is correct, because mendeleev’s model had all of the information correct in the first version. harmony is correct, because mendeleev’s model made predictions that came true.

If 22.5 liters of oxygen reacted with excess of hydrogen, how many liters of water vapor could be produced?