All matter is made up of atoms.  which sentence correctly describes atoms?   aan atom is the smallest particle of an element.  batoms are the smallest particle of a nucleus.  can atom is a substance that has been cut in half.  dall substances are made of the same atoms.

Salt in oceans comes from and of rocks

How many more valence electrons does sodium need to have a full outer valence shell

The zinc within a copper-plated penny dissolves in hydrochloric acid if the copper coating is filed down in several spots (so that the hydrochloric acid can reach the zinc). the reaction between the acid and the zinc 2h+(aq)+zn(s)→h2(g)+zn2+(aq) . when the zinc in a certain penny dissolves, the total volume of gas collected over water at 25 °c is 0.947 l at a total pressure of 743 mmhg . (vapor pressure of water is 23.78 mmhg at 25 °c .) what mass of hydrogen gas is collected? answer in appropriate significant figures