Why do silver accessories turn black when exposed to air?

Silver becomes black because of hydrogen sulfide (sulfur), a substance that occurs in the air. When silver comes into contact with it, a chemical reaction takes place and a black layer is formed. ... The oxidation of silver jewelry is a sign that it is really silv

its first and third is your answer i did the qustion the fourth isnt right

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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