Why do chemical properties change?

Chemical properties can change due to a variety of things. If you were to talk about Weathering, the chemical properties change when there is acid rain, water, CO2, and O2. Chemical Properties change when the chemical properties of an object change too.

some sources quote the lethal dose, for an average 170lbs opiate-naive individual is between 75 and 375 mg

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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