What did Dalton's atomic theory teach? A. Atoms can split into even smaller particles. B. All science can be explained by the existence of atoms. C. The smallest unit of matter is the atom. D. All matter comes from one kind of atom.

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.

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error

i do not get it   at all