In a chemical reaction, 300 grams of reactant a are combined with 100 grams of reactant b. both a and  b react to completion. how much will the product weigh?

400 grams. Due to the law of consevation of mass. It states that mass quantitu must remain constant.

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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