The 500 cubic centimeter of 0.250 M Na2SO4 solution, added to an aqueous solution of 15.00 grams of barium
chloride, resulted in the formation of a white precipitate of
barium sulfate. How many moles and how many grams of
barium sulfate are formed, respectively?

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

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